Uses: attaching signs, decorating, bread cutting machines, shower shelves, glass slabs on rattan furniture, towel racks, string lights and home decor. Made with many of passion in a small family business in Germany. Quality product. Positive side effect: low transport routes protect the environment. Versatile: mounting possible on most smooth, clean surfaces. Perfect hold on the glass. Clean the surface and press the suction cup. That’s it! Suction cup diameter: 50mm. Head diameter: 15mm. Thread: M4 x 10mm. Package contents: 8 suction cups and 8 knurled nuts.