Includes versatile wide gate spring hooks and attaches via heavy-duty webbing , These suction cups stick to smooth fiberglass surfaces like glass, boats, SUPs, cars and campers Versatile Usage - perfect for tie down applications where there isn't an anchor point, cleat or other device to anchor conventional tie downs. Suitable for smooth - These do stick and hold wonderfully on a smooth (like a car or glass), however, any plastic suction cup not stick if there is any texture to the whatsoever. It's the nature of the beast. If air can get in, the suction not hold because it relies on creating a vacuum. No Residues - No Glue -Strong Sticky gel base is added to the suction cup to provide stronger hold. The suction cup perform in cold or hot environment. Long Lasting hold, not come off it. Provide very strong grips on smooth . Control: Non-automatic colour:Black Material:plastic Package Contents: 2 set x Sucker Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.