Color: Black. Diameter: 3/8 in. Number in Package: 250 pk. Trade Size: 3/8 in. Electrical Fitting Type: Push-In Connector. UL Listed. For 1 or 2 cables. Installs easily snaps into KO using light finger pressure. Holds wire securely and meets and exceeds UL pullout tests. Simple to remove with a twist of a screwdriver. Knockout size: 1/2 inch.