BSA, Norton And Triumph Rocker Spindle Thackery Washer.
A double coil spring thackery washer used on the rocker spindle shaft of many models of British motorbikes like the following
BSA A7, A10, A50, A65, B25, B44, B40 and C15 models.
Triumph pre unit and unit models - T110, 6T, T120, TR6, T140, TR7, T150, T160.
Norton twins - Dominator, Atlas, Commando,
OD: 3/4" ID: 1/2"
Parts Nos. 70-1574, E1574, 67-0062, 40-0156, 06-7698, D12/950, NM18103