The M50 is the ultimate durable, functional, dive watch. Each watch is engineered from a block of solid 316L stainless steel & tested to a depth of 500M/1650FT, to make it virtually indestructible. The sapphire crystal is so hard, it is almost impossible to scratch, and Momentum’s® Long Life System offers approximately 10 years between battery changes. Outstanding performance. Outstanding style.
Check out this very in-depth review on the M50-DSS in the Watch Freeks forum.