Forever Suction Hooks- 8 Pack -You can always use more hooks for hanging items in the garage, on a boat or RV. These handy hooks serve as temporary or permanent fixtures on many surfaces, with a red warning indicator ring letting you know when you're losing suction power. Get hooked! Works on: glass, mirrors, tiles, metal, frosted glass, painted and grained wood, paint plate, antique bricks, painting board, PVC Board. The hooks comes in 3 sizes -- 4 large, 2 - medium and 2- small hooks.