Ikelite Underwater Digital Camera Housing 6037.12 Hermes Typewriter I can't figure out what

I can't figure out what the purpose of the clamp is

Frame size: 10×14 mm

This biography of the famous astronomer reveals the man who offered observational evidence supporting the theory of the expanding universe and demonstrated the existence of other galaxies

This has a 50 watt bulb

It will of course work on all Leica film cameras like the Leica Ia

Ikelite Underwater Digital Camera Housing 6037.12 Hermes Typewriter I can't figure out whatIkelite Underwater Digital Camera Housing 6037. 12, originally for the Sony VX2000 VX1000 cameras, it looks like a clear gallon sized paint can with cast aluminum end caps and a removable heavy metal base and handle. The entire unit can operate below 120ft. and weighs 22lbs. on dry land.