Finally the perfect base for your hot glass mosaics All weather aluminum Fusaics mosaic bases will not warp or rust and can withstand moderate outdoor conditions. Equipped with a bidirectional hook for maximum design flexibility. Easy to use bases require no sealing; simply rough the surface with sandpaper and use silicone adhesive to adhere your mosaic pieces.Made in the USA. Measures 13-5/8" x 8-5/8" Delphi Tip: Use a flat head screwdriver to press the hook through to the side you choose.