The Hit-Air Bungee Lanyard with Metal Clip is popular with Western and Endurance riders.

It's a single bungee strap with a metal clip attachment intended to clip to your saddle. The bungee part is stretchy and allows for some freedom of movement. 

Please be advised that we do NOT recommend clipping this to the D-rings on your saddle, as these do not provide solid attachment points to deploy your Hit-Air vest in the event of a fall.