The LockNLube® is the world's only rebuildable grease coupler. Rebuildable, not disposable, for the lowest lifetime cost. If it starts to leak, you simply replace the seal and jaws and it is as good as new. Check out this video to see how the rebuild kit works—grease goes in, not on, the machine! Each Rebuild Kit includes four hardened steel jaws and a threaded cone housing the rubber seal. Works with either the standard or XL LockNLube® Grease Coupler.