Features Clear Threads: The precise thread design on the screw provides maximum tightening force, perfectly and securely holding the item in place. Screw Nut Set: This M3 M4 M5 pan head hex socket screw nut combination set has tight and even threads that are less likely to deform and slip during rolling and installation. 304 Stainless Steel: The screws and nuts in this set are made of 304 stainless steel for fine workmanship and high strength. Large Quantity: There are 500 Pcs of screws and nuts with different functions in the set to meet your quantity needs. Widely Used: This screw kit can be widely used in computer repair and assembly, door and window assembly, automobile manufacturing and production. Specification:Item Type: Pan Head Hex Socket Screws Material: Stainless steel Size: Approx. 17.6 x 10.2 x 2.3cm / 6.9 x 4 x 0.9in Product Application: Fastening connection Product Specification: 500Pcs boxed M5 Width: Approx. 5mm / 0.2in M4 Width: Approx. 4mm / 0.16in M3 Width: Approx. 3mm / 0.12in Length: Approx. 8mm / 0.31in, Approx. 12mm / 0.47in, Approx. 16mm / 0.63in, Approx. 20mm / 0.79in Package List:500pcs per box Package List 500pcs per box