This tri-cup suction design with 3 vacuum super suction bases, can be firmly adsorbed on any smooth surface you want, please clean the dust in the glass or any smooth place first for long time use, and make sure the place and the suction cup are absolutely dry before use for a well suction. With this great suction power, it can be easily attached to any smooth surfaces you want, such as surfboard, skiing board, ceramic surfaces, car windshields, plate-glass doors, car windows, and more.