The Apeks TEK Gauge has a black face to help reduce glare and to preserve night vision in low-light environments. The numerals, intermediate markers and the single hand have a luminescent coating and glow when charged from a light source (usually a dive-torch).
The unit has a chrome-plated marine brass body with a tempered glass face. Its 52mm-diameter scale reads from 0-360 bar with a maximum working pressure of 300 bar, and weighed in at 200grm (without a hose) on my digital scale.
The instrument’s sealed and waterproof body houses a common Bourdon tube mechanism. For safety reasons the back of the body has a blow-out disc that’s designed to fail and release internal pressure should the Bourdon tube rupture, thus preventing the glass face fragmenting outwards.
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