Keep your projects secure and vibration-free with this 150-piece nylon insert lock nut assortment kit. Crafted from high-quality 304 stainless steel, these hex lock nuts offer excellent moisture resistance and corrosion resistance, ensuring they hold up reliably over time without rusting. The standard hexagonal shape provides uniform force distribution and a firm grip, making them easy to tighten without slipping during rotation. Each nut features a nylon insert that grips the bolt thread tightly, delivering dependable anti-vibration and anti-loosening performance ideal for mechanical assemblies and DIY fastening projects. The kit includes three sizes — 50 pcs of M4 (0.16" x 0.19"), 50 pcs of M5 (0.2" x 0.2"), and 50 pcs of M6 (0.24" x 0.24") — all neatly organized in a clear compartmentalized storage case for easy access and sorting. Whether you're working on machinery, automotive components, or home improvement projects, this versatile assortment has you covered.