Go to their site, there should have been directions on the package. Last time I used downriggers was many years ago. Play around with it you may get lucky as I've forgot most of what I knew. There should be a tension screw , the line /leader clips into/behind the wire thingy and you clip the other end either to the ball or I think you can also use it as a stacker and send it down the line .
BLACK MARINE PRODUCTS Black Downrigger Release Clip RC-95
Black Marine Products RC-95 release clip is made with the "Ring Snap" attaching bar for the ease and convenience of the angler to simply snap the clip in place on a downrigger. This release adapts for use in slider and stacking situations on the downrigger. It has an adjustable tension screw.
naps onto any downrigger or any weight. The release clip is made with the ''Ring & Snap'' attaching bar for the ease and convenience of the angler to simply snap the clip in place on a downrigger. Made of highly durable, flexible plastic, and stainless steel.