The Kirb-Perfect shower curb is a stay-in-place plastic form for building perfect shower curbs. Kirb-Perfect is designed to be used with the pan liner of your choice. It can be used with or without a 2 x 4 wood curb. With molded-in dovetail connecting lugs, this curb can be used for multiple length installations. Each piece of the Kirb-Perfect Shower Curb is easily cut with a hacksaw, PVC cutters or angle grinder. Supplied with two (1- 1/4 in length) and eight (3/4 in length) stainless steel shelf tapping screws and illustrated installation instructions. Kirb-Perfect is 4-9/16 in wide x 30 in long and 5-1/2 in height.