Works on Flat and Angled Curbs Assists Water Back Into Shower Rounded for Protection Accommodates 15/32" Gap. Clear Acrylic Frameless Shower Door Thresholds prevent water leakage and assists water back in towards shower. The Threshold can be applied with a Mildew Resistant Silicone Sealant. The rounded design protects feet from harm. The Acrylic Threshold can be used in conjunction with bottom door sweeps. Material: Clear Acrylic Length: 72" Height: 15/32" Width: 3/4"