Quantity : 20 pieces. Suction cups Ø 45mm with thread and knurled nut transparent. No drilling, no gluing required thanks to the vacuum effect, just clean the surface, it can fix to tiles, windows, car windows, etc. Suction cups with thread and knurled nuts for attaching plaques, blinds, signs, accessories and etc. Perfect hold on glass and any smooth, clean and non-greasy surface. If you have any questions, do not hesitate to contact us, we will do our best service for you.