These plastic tube inserts are designed to knock into the ends of tubes to act as feet or end plugs To keep water out and stop rusting from inside Easy and secure fitting Made from plastic Black colour All sizes measure in “mm”, a 20mm plug will sit flush outside on a 20mm outside box section steel The tops of the inserts are designed to sit flush with the outside of the tube whilst the shank has flexible horizontal ribs to suit a multitude of tube walls, in a range of both metric and imperial sizes. High quality product.
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