I find these helpful when stepping in or out of the tub, just to steady myself, not to put weight on it. It can hold pretty firmly on a very smooth hard surface, such as glass or larger tiles. But be aware that you will need to test it before using to support you, as with temperature changes, it can just drop off occasionally, as the suction seal loosens. But it's nice to have, and easy to install, on or off. One of them held so tightly, neither my husband nor I could get it to release.