GlobMarble SINK FAUCET KNOCKOUT SET FK8001 (4 pc) Sink Faucet Knockout Set FK 8001 Globmarble supplies professional grade casting molds which reproduce the structure and relief of natural stone to the smallest details. Molds made of two-component polyurethane or silicone rubber proved their high quality and durability. Durable polyurethane rubber faucet forms for concrete/cement counter top faucet knockouts. Faucet Forms cast a 1 3/8" diameter void in your concrete countertop for easy installation of faucet fixtures, control valves, and dishwasher vents. Self sealing, reusable for multiple concrete castings and tapered for easy removal. Leaves a 1- 3/8" void and 2 3/8" void for mounting hardware. 1 set- 4 molds. Rubber plug forms size: 2 x 1 3/8"(2.54cm) diameter x 2" tall (5 cm) approximately, 2 x 2 3/8"(5.08 cm) Big End diameter and 1 3/8" small end x 2" tall