Explanatory notes
… heading include : (1) Parts for military weapons , e.g., liners (tubes for barrels), recoil mechanisms and breeches … carriages, tripods and other special mountings for guns, machine‑guns, sub‑machine‑guns, etc., whether or not with … catches, cylinders (for revolvers), front and back sights, magazines. (3) Protective covers and protective cases , …