Steel drive-in end caps for square tubing 20 to 60 mm – form-fit closure for square tube profiles. For wall thicknesses from 1.5 to 3.0 mm, raw/ungalvanized; also available galvanised for 30 and 40 mm. With M8 internal thread in 40, 50, and 60 mm. Neatly seals open tube ends and rounds off sharp edges on railings and fences.