Side Entry Tubes with 10mm or half inch female thread and 10mm male thread to the base. A hollow tube with a side hole for our earthed braided lamp flex to come out. Our 5mm 3 core braided lamp flexes will fit through the hole (not the plain), you need a 3 core flex as this has an earth wire.  The Plastic grommet prevents the lamp flex from fraying and the black grub screw grips the flex inside the tube to stop it from pulling . Made from Solid brass and available in 3 finishes.