Bryan,
"Shark Jaws" or "Karm Forks" - similar items for the same job of gripping chain or wire pennants. Imagine a large pair of pliers, with the gripping end able to be raised above deck level or retracted flush with it. The jaws are opened or closed remotely from the Bridge by hydraulics. Usually fitted for'd of the towing pins which in turn are for'd of the stern roller.
"J-hook" or "chain chaser" - just a very large steel hook like a crane hook abut 1.5m high which can be lowered to the seabed (or under a chain being worked by another vessel) and pulled until it hooks onto rig chain or wire and permits the latter to be lifted/supported. Sometimes a grapnel of similar size is used to find chain on the bottom and this has a fluke design which, once the chain is hooked, prevents it running through the grapnel.
"Towing pins" - Just the same hydraulically raised/lowered pins that you'll find on any tug to limit transverse movement of a wire or chain. Sometimes, fitted in double sets (inner and outer) depending on the limit to be placed on transverse movement. Thus the inner set maybe twelve inches apart and the outer set maybe six feet apart.
"Stern roller" - large roller, free to turn, installed at the join of main deck and transom; the top of the roller just slightly proud of main deck level. These days extends almost the full beam at stern. Allows wires, anchors etc., to pass over stern without shredding the steelwork. ( They cut up wrecks with chains don't they.)
Does that help?
