THORN is written on the top of the crank housing. The number 6RS-13 is sramped on the bottom of the crank housing. The arm is 8 1/2 inches long.
The crank housing is 4 3/4 inches wide.
There are 3 holes in the rear of the crank housing, one at each end and one 1? (measured from the center of the end hole to the center of the adjacent hole.