Harmony Paddler's Mouth Horn These jaws show real teeth. 3 3/4" (9.5cm) diameter circular cleat has positive locking jaws that will secure up to 3/8" (1cm) thick line. Cam cleats lock down on line securely in one direction yet allow easy give or take in the other, making them ideal for use with anchor lines. Cleat is easily bolted or screwed to canoe decks.