Excellent material: Our self-locking nuts are made of high-quality stainless steel and nylon, which are corrosion resistant and help prevent loosening and twisting. Durable for long-term use. Nylon insert: Threaded hex nuts feature a nylon insert that resists loosening and keeps the nut securely in place during vibration. These threaded nuts are waterproof, rust-proof, and sturdy. Easy to store: Individual storage compartments allow for organized storage. The transparent box design provides clear visibility of the contents, even when containers are stacked. Strong and secure, the box will not open during transit. Wide range of applications: Stainless steel nuts can be used with bolts, threaded rods, and Allen screws. Ideal for use in furniture, cabinets, motors, textile machinery, workshops, and more. What you get: 170 pieces in 7 commonly used sizes: M3 (45 pcs), M4 (35 pcs), M5 (30 pcs), M6 (30 pcs), M8 (15 pcs), M10 (10 pcs), M12 (5 pcs). Product dimensions: 17.6 x 10 x 2.3 cm.