Package Include -- 20pcs x Compressed Spring Material -- 304 Stainless Steel. High elasticity, smooth surface, anti corrosion and rust ability can provide a durable, reusable and long service life. Specification -- Wire Diameter x Outer Diameter x Length Size -- Wire Diameter 0.5mm (0.02"); Outer Diameter 6mm (0.24"); Length 30mm (1.18"); Ideal Choice -- Our Small Compressed Spring are widely used in daily life repairment and maintenance, suitable for electronic products, pens, toys, tools, 3D printer and DIY project. Durable, high temperature resistant and anti-corrosion, superior longevity.