A 1917 United States National Army (USNA) enlisted men's collar disk. The bronze disk features the USNA device embossed at the center and arranged in a monogram style with the [U] and the [S] on the ...
BLC Bearlok Shrink Disc locks power-transmission components to keyless shafts more securely than conventional collars. Alloy steel, black-oxide coated; bores from 0.75 to 2.50 in., ODs from 1.985 to 1 ...