Listings show clamping forces from about 260 lb up to roughly 600 lb, with several products specifically listing 260 lb, 300 lb, 450 lb, and 600 lb values.
They use a pistol‑grip trigger (and often a quick‑release button) to move the jaw, allowing you to position the clamp, switch between clamping and spreading, and incrementally tighten with a single hand.
Common anti‑marring features include soft‑touch or non‑marring pads, grooved or textured jaw faces for grip, swivel/pivoting pads that align with the workpiece, and removable pads that can be replaced or removed to protect surfaces.
They adhere best to smooth, non‑porous surfaces such as shower walls, glass, doors, windows, tile, mirrors, metal, and plastic.
Throat depths shown in listings range from about 1 1/4 in to 3 5/8 in. Clamping or span capacities vary by clamp type and run from roughly 4 in up to about 42 3/4 in.
No drilling is required: clean the smooth surface, press the cup to expel air and lock it in place. To remove, lift or pull the release tab. Listings indicate the hooks are reusable and leave no residue.