pf2e.fyi
From Pathfinder Battlecry!, which isn't enabled.

Sailor's Collar (Greater)

ITEM 10
Price 850 gp
Usage worn
Bulk L

Veteran sailors like to wear this jaunty blue collar, tied with a small bow in the front and tucked into the belt. It can even save your life if you fall overboard. When wearing the sailor's collar, you gain a +2 item bonus to Athletics checks.

Activate—Gasp for Air (air, concentrate)
Frequency once per day
Trigger You fail a Swim check

Effect Your collar inflates, giving you something to breathe from. You can breathe underwater, and you gain a 10-foot swim Speed for 1 minute.

Effect: Gasp for Air

Pathfinder Battlecry!ORC