Hold tight on a granular surface of a dashboard. Effective suction time. 1 star less because if the quick release system is handy compared to the old version clip (need a single hand to install the device) impossible to simply remove their smartphone with a single hand pressing a button ... it must simultaneously push the rear of 2 plastic rods until the clamps return to their original place. No problem to maintain my Oneplus with his Diztronic hull.