CRL 1-1/8" Small Suction Cups with Metal Hooks by CR Laurence by CR Laurence. $16.83. Made of Crystal Clear Vinyl Metal Hook Will Not Rust Weight Capacity: 1 pound (.45 kg) CRL Vinyl Suction Cups contain U.V. stabilizers that protect the cup from yellowing in the sun. Cups generally adhere to smooth, non-porous surfaces with little effort. Designed to hold signs, radar detectors, thermometers, bird feeders, and so on. These clear vinyl cups can hold up to 1 lb. (.45 kg) safely.