. 900 x 900 White Slate Effect Square Shower Tray with Waste Summary We are proud to present you with this 900 x 900 White Slate Effect Square Shower Tray. Handmade from Cast Stone Resin for that traditional & truly timeless feel. Features. Square Shower Tray 900mm x 900mm Style Traditional Finish White Slate Effect Slip Resistant Traditional Cast Stone Shower Tray Handmade Waste Included.