The Blue Dog is a product that gives great functionality to your workbench when dogs are needed. Simply use a 2-1/2" hole saw to drill out a hole, sand the top edge, & press the Blue Dog down into the hole until flush. Detents allow easy & accurate height adjustment for any material thickness & the turntable feature allows great flexibility on your workbench. Another great product developed by a cabinet maker on the shop floor. See here for the 4-pack.