High QualityMade of durable 410 stainless steel for perfect corrosion protection, high hardness and stability. These stainless steel screws can be used indoors and outdoors. Suitable for metal, wood, plastic and other similar materials. Self-drilling tipThese self-drilling tips can be drilled directly into any metal surface without the need for pre-drilled holes. They can be easily removed with a screwdriver or drill. Phillips & NotchSelf-tapping screws have Phillips and notch on the screw head. This allows them to better prevent them from sliding sideways. Easy to install and save time. Convenient storage and sortingWith the included storage box, you can sort the metal screws neatly and conveniently. The sizes of the stainless steel screws are indicated on the cover, so you can easily find the size you want. 6 Mixed Sizes The set of different self-drilling screws includes 6 sizes: 20 pieces M4 .2*50mm/20pcs M4.2*38mm/20pcs M4.2*30mm/40pcs M4.2*25mm/50pcs M4.2*19mm/50pcs M4.2*13mm; 200 pieces in total, ideal for your various requirements. When choosing a metal screw, it is important to take into account the strength of the materials and the type of materials to be joined.