Material: ABS Bearing: 30lbs Pin Quantity: 4 Pin Size: 1.4mm x 15mm / 0.055" x 0.59" (D*L) Total Size: 50mm x 21mm x 13mm / 1.97" x 0.83" x 0.51" (L*W*H) Package Content: 20 x Non-Trace Picture Hangers Notes: 1 、Nails are very sharp, so please use the hooks carefully in order to avoid accidentally hurt fingers. 2 、Please keep the hooks away from children, place the product in safe area after use. 3.Some of the walls are loose on the surface, and when they knock on nails, they are easy to knock in and but provide terrible loads.Make sure you knock the hook and pull the hook. If you can't pull the hook, you can hang the picture frame safely. Do not continue to use the hook when you pull it out. 4.Just make sure you are using the right size when hanging items on the hooks