Fiberglass. Slip resistant floor. Simulated tile walls. Molded soap ledges. Molded seat 13"W x 21-1/2"D x 19"H (opposite of valve wall). Above the floor rough. Center drain. Complies with NAHB, HUD UM-73A, & ANSI-Z124.1.2. 6 year warranty. 8-1/2" Threshold.