TUSA

TUSA RS-681 (Yoke)

TUSA's compact, lightweight mid-range diaphragm reg with exhaust-noise-reducing tech and a MIFLEX hose standard.

Environmentally sealed

Sealed first stage chamber, protects against ice formation and contaminants in cold or silty water.

TUSA RS-681 (Yoke)
$719
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Released—
First stagediaphragm
BalancedYes
Environmentally sealedYes
Cold-water ratedNo
Connectionyoke
Max pressure—
HP / LP ports2 / 4
Adjustable 2nd stageYes
Weight—
Nitrox-ready (EAN40)—
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
  • Sequential Exhaust Assist (S.E.A.) technology reduces bubble noise and interference on exhale
  • Ultra-compact, elliptical low-profile second-stage case is genuinely lighter in the mouth than bulkier competitors
  • Ships standard with a MIFLEX braided hose instead of a basic rubber hose
Cons
  • Needs the separate EK-600 cold water kit for use below 50°F/10°C, it isn't cold-rated out of the box
  • DIN requires a separate conversion kit rather than being sold DIN-ready
  • TUSA doesn't publish a nitrox percentage rating for this model

TUSA’s site doesn’t list a current or past “RS-611 Alpha,” so this entry covers the RS-681, which TUSA itself describes as its latest compact mid-range regulator and the natural step below the RS-1001. It’s aimed at divers who want a smaller, lighter reg for warm-water and travel use without stepping down to TUSA’s entry-level line.