Materials and surface treatment - Corrosion-resistant 304 stainless steel ensures durability in humid or indoor environments. SPECIFICATION:Product Name: Pan Head Self Tapping Screws Kit Set for Metal, WoodThread Diameter: M1/M1.2/M1.4/M1.7(Thread Dia x Pitch)Screw Length:M1x3,M1x4,M1x5,M1.2x3,M1.2x4,M1.2x5,M1.4x3,M1.4x5,M1.7x5,M1.7x6Surface Treatments: Black OxideMaterial: 304 Stainless steelQUANTITY INCLUDED - 1000Pcs x Pan Head Self Tapping ScrewsADVANTAGE - Requires pre-drilling in metal substrates, optimized for soft metals like aluminum/copper to eliminate thread stripping. Also widely used in wood, furniture, and other purposes.DESIGN - Deep cross recess minimizes cam-out, ensuring stable engagement with screwdrivers for precise installation. Balances performance and affordability, suitable for furniture assembly, electronic device mounting, and DIY projects.