Rigging Chain Chokers go over the steel beam, one end goes through the shackle at the other end and attaches with another shackle to the down cable. Rigging Chain Chokers are used when it is necessary to hang a load off of one side of a beam in a speaker rigging project, instead of hanging the load centered on a beam. Chain is Grade 100 heat treated alloy steel. Includes one length of chain and three shackles each with a #16 solid steel wire. Design factor is 10:1. Other lengths and chain sizes available upon request.