Whitworth 55°: 4G, 4 1/2G, 5G, 6G, 7G, 8G, 9G, 10G, 11G, 12G, 13G, 14G, 16G, 18G, 19G, 20G, 22G, 24G, 25G, 26G, 28G, 30G, 32G, 36G, 40G, 48G, 60G, 62G. - It is 55 degree & 60 degree thread / screw pitch gauge gage with lock up device.
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