Package contains: 20pcs thread suction cup 4cm, with knurled nuts. Diameter of the cup is 40mm. Thread height is 6mm. This thread suction cup is made of high-strength transparent PVC plastic, soft, , waterproof, not easy to fall. Suitable for glass, mirror, ceramic wall, tile, smooth metal , bathroom tiles wall, kitchen tiles wall, glass shower screen, glass window. Don't work on pitted/uneven surfaces. TIPS: Make sure the object is clean, smooth, no dirt and no oil stains. You can dip a little bit of water in the inside of the sucker before you stick the sucker, so as to stick more firmly. Other Uses: Can be used to fix insulating covers to the inside of . Or use these suction cups to attach windbreak along the lower side of motorhome, within an awning. Use them in the car to hold sun shades up to shade the kids. Use them in the car to hold sun shades up to shade the kids. Very good grip when attaching to glass. Can be used as suction pads for glass tabletop on garden rattan table. Great small sucker hooks to hold up Christmas lights on a window. Can hold homemade black-out blinds in conservatory. Easy To Use. No drilling needed. Great suction pads for hanging things when you don't want to drill or use Nylon Sticker. Not only used for daily household, but also for holiday decoration and hanging handmade crafts. Colour:transparent Material:plastic Package Contents: 20pcs thread suction cup 4cm Only the above package content, other products are not included. Note: Light reflection 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.