Apeks

Apeks XTX100 (DIN)

Apeks's mid-tier cold-water workhorse, built around the over-balanced FST diaphragm first stage, now sold mostly as remaining new-old-stock.

Environmentally sealed, cold-water rated

Sealed first stage keeps water and ice crystals out of the internal mechanism, the standard for diving below 50°F/10°C.

No image yet
$399.95
Released
First stagediaphragm
BalancedYes
Environmentally sealedYes
Cold-water ratedYes
ConnectionDIN
Max pressure300 bar
HP / LP ports2 / 4
Adjustable 2nd stageYes
Weight
Nitrox-ready (EAN40)Yes
Octo includedNo

"HP / LP ports" is the number of high-pressure and low-pressure ports on the first stage, which caps how many accessories (transmitter, SPG, inflator, second second-stage) you can run at once.

Pros
  • Over-balanced FST diaphragm first stage keeps breathing effort consistent as tanks empty
  • Environmental dry system and a cold-water rating below 10C/50F make it a genuine cold-water reg, not just a warm-water design
  • Diver-adjustable opening effort control knob on the second stage
Cons
  • Discontinued around 2018 in favor of the FSR-equipped XTX200, so it's largely sold as remaining stock rather than a current model
  • No octopus included in the base listing
  • Weight isn't reported consistently enough across retailers to publish a reliable figure

The XTX100 was Apeks’s mid-tier cold-water regulator, sitting between the entry-level XTX40/XTX50 and the high-flow XTX200. It’s since been discontinued in favor of the FSR-equipped XTX200, so today it mostly turns up as new-old-stock or used gear, a good value if you can find one, but not a reg to plan a long-term parts-and-service relationship around.