Arlington Snap2IT® Cable Connector, Straight, 3/8 in Trade, 1/2 in Knockout, Cable Openings: 0.45 to 0.612 in, Aluminum/Steel/Flex/AC/AC90/ACG90/HCF/MC/MCI/MCI-A Cable, Snap-In Connection, Die Cast Zinc, Silver, 1 in Dia x 1.41 in L Dimensions. Arlington Snap2IT® connectors are designed for safe and fast installations of flex, MC, AC and HCF cable and cover the widest cable ranges in the industry. They save time too-about 17 s per fitting. Just snap the fitting onto the cable, then into the electrical box. No tools are required for the installation.