plastic self tapping screw Surface Treatment: Polished or Galvanized High Quality & Competitive Price Prompt Delivery Hex self tapping screw with bonded washer 1.Usage: Industrial construction, architecture, foundry, furniture-making or furniture repair, interior or exterior upholstery/decoration, packing boxes and so on2.Surface Treatment: Polished or Galvanized3.Shrank: Smooth, Grooved, Spiral, ...