Our Phillips hex head SEMS assembly screws are integrated fasteners pre-mounted with a plain flat washer and a spring lock washer on the screw shank in one finished piece, eliminating the trouble of manually matching separate washers during on-site assembly. The product adopts an external hex flange head combined with a Phillips cross recess dual drive design, compatible with both spanners and cross screwdrivers, which greatly improves assembly flexibility for different working scenarios.
This series of combination screws are manufactured with precision thread rolling and cold forging forming technology. Standard materials include high-strength carbon steel with electro-galvanized treatment and SUS304 / SUS316 stainless steel. The galvanized carbon steel version features bright silver surface and stable anti-rust performance for indoor equipment assembly; stainless steel variants deliver outstanding resistance to rust, acid, alkali and salt fog, perfectly fitting outdoor facilities, coastal projects, humid workshops and corrosive working environments. Full metric specifications ranging from M3 to M10 are consistently stocked in our warehouse, supporting bulk batch shipment and non-standard customized length, thread pitch and head size according to customers' engineering drawings.
Unlike loose screw-washer sets that are easy to lose scattered small accessories during packaging, transportation and assembly, our integrated SEMS structure locks the two washers onto the screw shaft with a retaining groove, so the gaskets will never slip off or separate even after repeated disassembly and vibration. It effectively reduces accessory management costs for automated production lines, electrical factories, cabinet manufacturers and mechanical assembly workshops, and shortens single-piece fastening operation time significantly.
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