One Pismo Clam Gauge. 4 1/2" inch. If the clam goes through the gauge, properly rebury it so it can thrive. If it doesn't go through, it is good to keep. Made from 6061 T6 Aluminum with ergonomic fingers and thumb grip, CNC machined, chamfered, de-burred, and the aluminum is brushed. Includes holes so you can attach a string so it is easy to find.