DB Hercules main lifting block
The Brown & Root DB Hercules (and its sister, the Atlas) had Clyde D76 cranes capable of lifting 2,000 tons. This was taken in the Persian Gulf, November 1978. Here's the main lifting block being prepared to lift an entire platform jacket -- we would use the small hook at left to pick up the wire slings and place them over the main hook.
Picture added on 28 July 2009 at 12:24