Abstract: The present document relates to retention collars for use with weight plates and a cylindrical element, such as a barbell, designed to receive the weight plates. The retention collar comprises a body with an expansion opening, and an opening mechanism. The opening mechanism comprises a first radial tab extending from the body adjacent to a first side wall of the expansion opening and a second radial tab extending from the body adjacent to a second side wall of the expansion opening with a tab-receiving aperture for receiving the first radial tab therethrough. When the first and second radial tabs are squeezed together, the diameter of the center aperture increases to receive the cylindrical element therethrough. When the opening mechanism is released, the center aperture returns to its original diameter and retains the weight plates on the barbell.