So here are a few pictures of how I do mine after I buy them. If they come with the swivel to attach your leash I remove that and use the solid ring fir the leash. You just have to re feed the chain the other way. Then reattach the two chain ends with a small SS carabiner. It must be snake enough to pass through the hole of the prong connection. Before attaching carabiner you must install a snap hook of some type, again SS is best. Snap hook connect to other end of prong assembly.
Alrighty then. From a lifetime with horses I know the weakest link is what breaks and I didn't want to use anything that would mess up that "martingale" design or use a ring that might stretch out. Yea! I'll work on this. Thanks a million.