Phillips Flat Head Screws: The self-tapping screw set is suitable for home, office or industrial use. The sharp tips can easily pierce plastic, soft metal, wood, wall, etc. Quick and easy to countersink, suitable for home, office or industrial use. Anti-rust Material: The countersunk screws are made of sturdy and durable carbon steel, well coated with a black anti-oxidation layer, which has strong anti-rust and anti-corrosion performance. So even in a humid environment, it can be used with confidence. Convenient Storage: The flat head screws of different sizes are stored in a counterpart of the PVC storage box, convenient for storing and sorting. Package Content: Color: Black Quantity: 230pcs M3.5*16---30pcs M3.5*20---30pcs M3.5*25---35pcs M3.5*30---35pcs M3.5*35---30pcs M3.5*40 ---35pcs M3.5*50---35pcs Widely Used: This self tapping screw assortment is widely used for home and office appliances, workplace fasteners, electrical appliances, car or boat assembly, machinery, furniture, crafts.