These couplers are made of a low carbon steel - easy to drill and stronger
than cast iron. They can also be welded. These are lost wax castings that
look nice and operate well.
There are two drill dimples cast on top of the coupler. One in the shank for the frame mounting bolt and the other above the drop latch for fastening a hook onto the drop latch. This is for top release type couplers if so desired.
The shank measures 15/16 inches wide by .725 inches high for easy mounting into a rectangular tube frame. (see price list).