Question Apeks first stage identification

[JMBL]

What I get from the manual, this reg is not designed for cold water use. Any experience on that?

Please, define cold : cold as in freezing, i.e ice diving or close to that, or cold as requiring a dry suit with a cozy undersuit ?

Some buddies of mine dive those regs on a regular basis, in 12°C, up to 60m/200 feet and often beyond.

 

[velky chobot]

Please, define cold : cold as in freezing, i.e ice diving or close to that, or cold as requiring a dry suit with a cozy undersuit ?

Some buddies of mine dive those regs on a regular basis, in 12°C, up to 60m/200 feet and often beyond.

My bad, cold as in below 10°C, usually around 4°C, fresh water..

 

[JMBL]

My bad, cold as in below 10°C, usually around 4°C, fresh water..

Cold indeed, outside my experience, sorry.

 

[DiveGearExpress]

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[Centrals]

What I get from the manual, this reg is not designed for cold water use. Any experience on that?

FST has the dry chamber for the spring so it is for cold water.
FSR, DS4, DST are all cold water reg.

FST used to be the top of the range until replaced by FSR. I believe it is no longer in production.