Marathon GSAR Manuel page 5

TRITIUM GAS TUBES
The GSAR uses self-contained tritium gas tubes to ensure constant
visibility in low light situations. A gas tube is placed on each hour marker
and hand. These tubes are self-illuminating and contain an isotope of
hydrogen, that will not dull down over time like photo-luminescent paint.
CONSTANT ILLUMINATION
WATER RESISTANCE
The GSAR is made from 316L surgical-grade stainless-steel with a screw-
down crown and a synthetic sapphire crystal that allow it to operate while
submerged down to 300 meters or 1000 feet underwater.
30 ATM – 300 M (1000 FT)