Highly effective and exceptionally well-constructed, the Clarkspoon Diving Planers are designed to help you control your trolling depth at just about any trolling speed. Simply attach your main line to the brass ring and your leader to the hole in the blade. After feeding your leader and lure into the water, submerge the weighted end of planer into water at downward angle and it will dive. The planer will trip when a fish strikes and return to the surface. Planers are a particularly useful tool when trolling with lightweight lures like spoons or jigs that will not dive deeply on their own.