Description: Made of stainless steel washers, durable and strong, rust resistant, long lasting. These washers help to prevent bolts or nuts from pulling through a surface. Fitment: home, automotive, and shop use. Includes 9 sizes common use flat washers: 100 pieces M2,100 pieces M2.5,100 pieces M3, 100 pieces M4, 60 pieces M5, 40 pieces M6,50 pieces M8, 20 pieces M10, 10 piece M12. Specification: Size: Approx. Inner diameter x Outer diameter x Thickness M2: 2x5x0.3mm/0.08x0.20x0.01inch M2.5: 2.5x6x0.5mm/0.10x0.24x0.02inch M3: 3x7x0.5mm/0.13x0.28x0.02inch M4: 4x9x0.8mm/0.12x0.35x0.03inch; M5: 5x10x1mm/0.20x0.39x0.04inch; M6: 6x12x1.6mm/0.24x0.47x0.06inch; M8: 8x16x1.6mm/0.31x0.63x0.06inch; M10: 10x20x2mm/0.39x0.79x0.08inch; M12: 12x24x2.5mm/0.51x0.94x0.10inch; Package Includes: 100 pieces M2 flat washers 100 pieces M2.5 flat washers 100 pieces M3 flat washers 100 pieces M4 flat washers 60 pieces M5 flat washers 40 pieces M6 flat washers 50 pieces M8 flat washers 20 pieces M10 flat washers 10 piece M12 flat washers