Made from durable plastic, these mini grommets have an overall diameter of 1" to 1-1/4" which takes up minimal surface area on any desk or workstation. The tab opening in the grommet is 5/16" to 1/2" (depending on the model) which accommodates small cables including telephone, fax and USB cords. Each grommet's canter tab and be removed for added space for additional cables and wires up to 7/8" to 5/8" (depending on model).