This spindle has a single ⅝″ course thread to accommodate an insulator and a shaft and longer thread totalling 4⅛″ to pass through the thickness of a pole arm. The spindle is secured by square nut.
The Insulator Spindle No.8 for a single insulator. Fitted in pairs in wall bracket as in the lower photograph or on the arms of a terminal pole. The Spindle No.8 is used in preference to a straight type four to reduce the torsional effect on the bracket from a long span of wire.