DockLocks SUP and Surf Board Lock One Size

If your board has a recessed leash plug, simply clamp the jaws around the leash plug bar
If you don't have a leash plug, install the included cleat in your Fin Plate (Fin Box), then clamp the jaws onto the cleat
Now, thread the cable through the cable ring on top of the jaws
Wrap the 10' coated steel-wire cable around a secure object and insert the end in the four-number combination lock spool
Lock the cable to a roof rack, park bench, bike rack, lamp post, etc. The possibilities are endless