Staples are used to attach NMC (non-metallic cable) or BX (armored) cable to wooden struts. The RX Series is used for Romex and the BX Series is used for Romex and BX. The SEU staple is used for service entrance cable and is available in 100 packs. For electro galvanized specify G (i.e. RXG50, BGX or SEU63G). Plastic Insulated staples are used for coaxial cable, bell wire, thermostat wire, telephone wire and Romex.