How to Choose a Scuba Regulator: Types, DIN or INT, Prices
What a scuba regulator is and how to choose one: first stage, cold water, DIN or INT, weight, nitrox and octopus, plus every regulator we sell with its price.
Your regulator is the piece of gear you breathe from for the whole dive. So the question is not "which regulator is best" but "which one fits the water I dive in, the tanks I use and the way I travel".
This guide sums up PADI's advice on choosing a regulator and the facts from each brand's official site. Then it sorts every regulator and octopus we sell by the kind of diving it suits, with the prices on our site.
What is a scuba regulator?
PADI puts it simply: a regulator lets you breathe underwater. A regulator set has a few parts:
- First stage: attaches to the tank valve, reduces the tank pressure to an intermediate pressure and sends the air to several hoses.
- Second stage: the mouthpiece you breathe from. PADI says it is also called a demand valve, because it gives you air when you demand it, when you inhale.
- Alternate air source (octopus): a spare second stage for sharing air when you need to help another diver. PADI notes it is sometimes built into the BCD inflator instead.
- Pressure gauge (SPG): connects to a high-pressure port on the first stage and shows how much air you have left. A PADI article says a diver must always carry an SPG along with a dive computer.
- Low-pressure hose to your BCD inflator, and another to your drysuit if you wear one.
How to choose a regulator, step by step
PADI's key point: choose a regulator that gives the performance you need for the places you will dive. Then try your top choices on a tank to feel how they breathe, and check the mouthpiece fit.
1. Warm water, cold water or both
PADI explains that environmental seals keep salt, sediment and other contaminants out of the first stage and help stop the parts inside from freezing in cold water. Each brand does this its own way:
- SCUBAPRO MK25 EVO first stages carry XTIS (Extended Thermal Insulating System), which SCUBAPRO says delays ice formation.
- Apeks lists XL4 OCEA, EVX200 and EVX Tungsten as certified for cold-water use (EN250A).
- Aqualung gives Helix Pro, Helix Compact Pro and the Leg3nd family a permanent dry chamber against freezing. Aqualung marks Titan, Helix and Helix Compact for warm water.
If you only dive warm, tropical water, a warm-water model is enough. If you also plan colder trips, pick one the brand marks for cold water.
2. First stage: piston or diaphragm, balanced or over-balanced
Two designs are in our range:
- Piston: every SCUBAPRO MK25 EVO first stage uses an air-balanced piston. SCUBAPRO says the airflow stays constant whatever your depth, tank pressure or breathing rate.
- Diaphragm, over-balanced: Apeks EVX200 and EVX Tungsten, and Aqualung Helix Pro, Helix Compact Pro and the Leg3nd family. Aqualung says the over-balanced design reduces your breathing effort regardless of depth or tank pressure, and Apeks says it raises the hose pressure faster than the water around you as you descend, which it says gives superior performance at depth. Apeks also over-balances the XL4 OCEA first stage.
PADI's regulator page doesn't compare the two. Its advice works for both: hook your top choices up to a tank and breathe them.
3. Second stage: adjustments and size
PADI says adjustable second stages let you fine-tune breathing so it stays as easy as possible, and a dive/predive switch makes the second stage less sensitive for a while so it doesn't free-flow. On our models you will see:
- One switch: a Venturi switch only, as on Aqualung Titan, Helix, Helix Compact, Helix Pro and Leg3nd, or a venturi lever only, as on Apeks XL4 OCEA.
- Two controls: a Venturi switch or lever plus a breathing-effort adjuster, as on SCUBAPRO's systems, Apeks EVX200 and EVX Tungsten, Aqualung Helix Compact Pro and Leg3nd Elite. Aqualung aims the Leg3nd Elite's independent micro-adjustments at advanced divers.
- One control for both: Aqualung's Master Breathing System on the Leg3nd MBS sets the Venturi effect and the inhalation effort in a single turn.
- A smaller second stage: Aqualung calls the compact second stage of the Helix Compact and Helix Compact Pro ideal for smaller faces, such as those of women and younger divers.
New to diving? The model Aqualung says is especially suited for beginners is the Titan.
4. DIN or INT (yoke)
PADI explains that regulators connect to the tank valve with either a DIN (screw-in) or a yoke (bracket) system, and that adapters exist to make DIN regulators work with a yoke valve. INT is the same yoke clamp. PADI's advice: know which connection is typical for tanks in your area.
- Most of our regulators come in DIN or INT; you choose one per set.
- SCUBAPRO MK25 EVO / A700 and MK25 EVO BT / G260 Carbon BT are listed in INT only. The SCUBAPRO MK25 EVO / G260 Sidemount Kit is DIN only.
- Aqualung lists a maximum working pressure of 300 bar in DIN and 232 bar in yoke.
Not sure which your dive centre's tanks use? Ask them, or ask us on LINE before you order.
5. Weight and travel
If you fly to dive, weight matters. The brands measure it differently, so compare within a brand:
- Aqualung first stage only: Titan 460 g DIN / 690 g INT · Helix and Helix Compact 475 g / 700 g · Helix Pro and Helix Compact Pro 525 g / 740 g · Leg3nd, Leg3nd MBS and Leg3nd Elite 747 g / 957 g. In every one, DIN is the lighter version.
- SCUBAPRO whole system: MK25T EVO / S620 X-Ti 0.85 kg in DIN, which SCUBAPRO calls ultralight thanks to its titanium first stage and barrel; MK25 EVO / S620 Ti 0.96 kg in the White DIN version.
- Size: Aqualung calls the Helix Compact Pro the smallest and most compact regulator it has ever produced. A braided hose, as on Helix and Helix Pro, is flexible and easy to travel with, according to Aqualung.
6. Nitrox
PADI says most regulators can be used with enriched air (EANx), but some manufacturers require their regulators to meet oxygen service standards for gas above 22 percent oxygen. What our brands state:
- SCUBAPRO: up to 40% on every system we sell.
- Aqualung and Apeks EVX: up to 40% O₂ when new, out of the box (21% in Europe).
- No figure in the brand information we have: Apeks XL4 OCEA and Aqualung ABS Octopus. Ask us before you dive nitrox with them.
7. Service and care
PADI advises having your regulator professionally serviced to the manufacturer's specifications, or sooner if you see damage, or it starts to breathe hard or leak air. Register the warranty with the manufacturer straight away. Aqualung calls for a service every 2 years on the Helix and Helix Pro. For the other models, the brand information we have gives no interval, so ask us on LINE.
After every dive, PADI recommends:
- Rinse gently in fresh water as soon as you can, with the first-stage dust cap firmly in place. Don't press the purge button while rinsing.
- Let it dry completely, out of direct sunlight.
- Store the hoses in large, gentle curves, not tight loops.
Care for the rest of your gear is in How to wash and store your dive gear.
Buy a full set or the parts?
PADI suggests trying a few regulators, then picking the one, or the complete package, that works for you. In our shop you can buy:
- Regulator only: first stage and second stage. Add an octopus and a gauge separately.
- Stage 3 sets (Aqualung): the regulator plus an octopus. On the Helix Pro and Helix Compact Pro Stage 3, the octopus comes unassembled, so it and the pressure gauge can go on the right or the left, as your training agency requires. Aqualung lists no pressure gauge in the Stage 3 sets.
- Packs (Aqualung): the regulator, an octopus, a pressure gauge and a bag.
- Sidemount kit (SCUBAPRO): two complete regulators with two compact gauges, the hoses and a regulator necklace.
Still renting? A PADI article suggests starting with the basics, such as mask, fins, boots and computer, and buying the bigger items once you have a better idea of what suits you underwater. For the full order, see our scuba gear list for beginners.
How to choose an octopus
The octopus is the spare second stage for an out-of-air buddy. PADI says it is generally a bright colour, such as neon yellow, so every diver can spot it underwater. Where to clip it, which side and how to check it before a dive are a topic of their own; for a quick look, watch our octopus video.
- Match it to your regulator: Aqualung made the Leg3nd Octopus to match the Leg3nd second stage, the Helix Pro Octopus to perform like the Helix Pro, and the Calypso / Titan Octopus to go with the Titan.
- For travel: Aqualung made the Helix Compact Pro Octopus small and compact, on a braided hose that packs easily.
- Either side: the ABS Octopus has a 120° angle between hose and mouthpiece, so it works from the right or the left without kinking the hose.
- On a SCUBAPRO or Apeks regulator, ask us on LINE which octopus to add.
Our regulators: which one suits you
We are an authorised dealer for SCUBAPRO, Apeks and Aqualung. Below, every regulator and octopus we sell is sorted by use, based on what each brand states. Prices are the prices on our site on 16 October 2026; the product page always has the latest, and we confirm price and stock on LINE when you order. To compare specs line by line, see Compare regulators and Compare octopuses.
Starting out and warm water
| Model | Strengths / who it suits | Price on our site |
|---|---|---|
| Aqualung Titan | Especially suited for beginners, according to Aqualung · easy to maintain, compact, Venturi switch · warm water | ฿15,680 |
| Aqualung Helix | Aqualung's mid-range model · braided hose, service every 2 years · warm water | ฿17,490 |
| Aqualung Helix Compact | Small, light and travel-sized · compact second stage for smaller faces · warm water | ฿20,590 |
Warm and cold water
| Model | Strengths / who it suits | Price on our site |
|---|---|---|
| Aqualung Helix Pro | Balanced first and second stage, ACD, dry chamber · cold and warm water · braided hose, service every 2 years | ฿21,890 |
| Aqualung Helix Compact Pro | The smallest regulator Aqualung has made (according to Aqualung) · for frequent travellers and smaller faces · Venturi and cracking-effort controls | ฿25,090 |
| Aqualung Leg3nd | For divers who put performance first · dry chamber and de-ice ribs for cold water · Venturi switch you can work in gloves | ฿29,390 |
| Aqualung Leg3nd MBS | Leg3nd with one control that sets Venturi and inhalation effort together | ฿34,490 |
| Aqualung Leg3nd Elite | Made for challenging and extreme dives · independent micro-adjustments Aqualung aims at advanced divers | ฿37,990 |
| Apeks XL4 OCEA | Made from recycled and bio-based materials (Apeks) · over-balanced, sealed first stage, EN250A cold water · compact second stage · watch our review | ฿30,890 |
| Apeks EVX200 | Over-balanced first stage, 7 ports, reversible second stage · breathing adjuster you can turn in gloves · EN250A cold water | ฿38,590 |
| Apeks EVX Tungsten | The same core features as EVX200, per Apeks · brass first stage with heat-exchanging ribs · black | ฿47,090 |
| SCUBAPRO MK25 EVO / S600 | Piston first stage with XTIS · SCUBAPRO says the pair is well known for its low work of breathing | ฿31,285 |
| SCUBAPRO MK25 EVO / G260 | SCUBAPRO's largest second-stage case and diaphragm · hose from the left or right · cold water and tech set-ups | ฿32,185 |
| SCUBAPRO MK25 EVO / S620 Ti | An all-purpose, all-weather system · smaller and lighter than the S600, same-size diaphragm, titanium barrel · watch our review | ฿38,165 |
| SCUBAPRO MK25 EVO / A700 | Full metal second stage with a larger diaphragm · from tropical seas to polar ice, per SCUBAPRO · INT only | ฿41,325 |
| SCUBAPRO MK25 EVO / A700 Carbon BT | The A700 with a handmade carbon fibre cover and Black Tech finish · INT or DIN | ฿47,690 |
| SCUBAPRO MK25 EVO BT / G260 Carbon BT | The G260 tech system with a carbon fibre cover and Black Tech finish · padded case · INT only | ฿53,700 |
| SCUBAPRO MK25T EVO / S620 X-Ti | Titanium first stage that SCUBAPRO says will not corrode even in concentrated salt water · 0.85 kg DIN system | ฿96,925 |
Sets: regulator with an octopus
| Model | Strengths / who it suits | Price on our site |
|---|---|---|
| Aqualung Helix Pro Stage 3 | Helix Pro + octopus on a 1 m yellow hose, fitted left or right as your training agency asks | ฿30,690 |
| Aqualung Helix Compact Pro Stage 3 | Helix Compact Pro + its octopus on a 1 m hose · for travel and smaller faces | ฿32,890 |
| Aqualung Leg3nd Stage 3 | Leg3nd + octopus | ฿39,490 |
| Aqualung Leg3nd MBS Stage 3 | Leg3nd MBS + octopus | ฿43,890 |
| Aqualung Pack Helix Pro | Helix Pro + octopus + pressure gauge + bag | ฿35,090 |
| Aqualung Pack Leg3nd Elite | Leg3nd Elite + octopus + pressure gauge + bag · for advanced divers, per Aqualung | ฿50,490 |
Sidemount
| Model | Strengths / who it suits | Price on our site |
|---|---|---|
| SCUBAPRO MK25 EVO / G260 Sidemount Kit | Two MK25 EVO DIN 300 first stages, two G260 second stages, two compact gauges, hoses · SCUBAPRO made it for cold-water and technical diving · not a first regulator | ฿70,345 |
Octopus
| Model | Strengths / who it suits | Price on our site |
|---|---|---|
| Aqualung Calypso / Titan Octopus | Made to go with the Calypso and Titan · side openings against free-flow in current · 1 m hose | ฿7,290 |
| Aqualung ABS Octopus | 120° hose angle, works on the right or the left · compact · 1 m yellow hose | ฿8,590 |
| Aqualung Helix Pro Octopus | Performs like the Helix Pro second stage, per Aqualung · lip shield · 1 m yellow hose | ฿8,590 |
| Aqualung Helix Compact Pro Octopus | Small and compact for dive trips · 1 m yellow braided hose | ฿9,390 |
| Aqualung Leg3nd Octopus | Matches the Leg3nd second stage, per Aqualung · 1 m yellow Aqua Flex hose | ฿9,990 |
Before you order a regulator, always message us on LINE first. Tell us where you dive and whether your tanks use DIN or INT. We ship within Thailand, free from ฿2,000; below that, a shipping fee applies. Details are on our shipping and returns page.
Bottom line
Start with where you dive: warm water only, or cold water too. Then match DIN or INT to the tanks you use, decide how many breathing controls you want, and check the weight if you travel. Add an octopus, or buy a set that already has one. If you can, breathe a few regulators on a tank before you decide.
New to diving? Watch our 5 things every new diver should know.
FAQ
What is a regulator in scuba diving?
The gear that lets you breathe underwater, PADI explains. The first stage on the tank valve reduces the tank pressure, and the second stage in your mouth gives you air when you inhale. A full set also has an octopus for your buddy and a pressure gauge.
Which regulator brand should I choose?
No brand suits every diver. In our shop, SCUBAPRO's systems all use a piston first stage with XTIS, the Apeks regulators we sell have over-balanced first stages and EN250A cold-water certification, and Aqualung runs from the Titan, which it says is especially suited for beginners, to the Leg3nd Elite for advanced divers. Choose by where you dive, then try how they breathe.
How much does a scuba regulator cost?
On our site on 16 October 2026, regulators run from ฿15,680 (Aqualung Titan) to ฿96,925 (SCUBAPRO MK25T EVO / S620 X-Ti), and an octopus from ฿7,290 (Aqualung Calypso / Titan Octopus) to ฿9,990 (Aqualung Leg3nd Octopus). Each model's price is in the tables above; we confirm price and stock on LINE when you order.
DIN or INT: which should I buy?
The one that matches the tank valves where you dive. DIN screws into the valve and INT (yoke) clamps onto it. PADI notes that adapters exist to make DIN regulators work with a yoke valve. Ask your dive centre, or us, before you order.
Which regulator is good for beginners?
Aqualung says its Titan is especially suited for beginners, and calls it easy to maintain, compact and comfortable. The SCUBAPRO Sidemount Kit and the Aqualung Leg3nd Elite are not first regulators: SCUBAPRO made the kit for cold-water and technical diving, and Aqualung aims the Leg3nd Elite's micro-adjustments at advanced divers.
How often does a regulator need a service?
PADI says to follow the manufacturer's schedule, or go sooner if you see damage, or it breathes hard or leaks air. Aqualung calls for a service every 2 years on the Helix and Helix Pro. For other models, ask us on LINE.
Can I use my regulator with nitrox?
PADI says most regulators can, but some manufacturers require oxygen service standards for gas above 22 percent oxygen. SCUBAPRO rates its systems up to 40%, and Aqualung and Apeks EVX rate theirs up to 40% O₂ when new, out of the box (21% in Europe). Ask us before you dive nitrox.
Do I need an octopus?
PADI lists the alternate air source as part of a regulator set: a spare second stage for sharing air with a diver who needs it. Some divers have it built into the BCD inflator instead. Our Stage 3 sets and Packs come with an octopus.
