A cost-effective alternative to Aerotight® fasteners, this RS PRO self-locking nut has a nylon insert that compresses when the mating bolt is inserted, providing good resistance to vibrations and torque. The nylon insert can withstand temperatures up to +250°C and provides a 360° sealing to help prevent gas and fluid leakage, making the lock nut especially suited for use in heat exchangers.

The fastener is made of mild steel grade 8.8 and conforms to ASTM (American Society for Testing and Materials) standards DIN 985, meaning it can withstand tension of up to 800 N/mm² and is fit for general mechanical, railroad and industrial settings. Zinc-plating on the lock nut ensures good resistance to corrosion and rust.

Nylon-insert lock nuts offer highly effective sealing even when exposed to leaking water, oil, solvents and other liquids. They're commonly used by DIY motor enthusiasts, builders, roofers and joiners.

Unlike conventional fasteners, lock nuts, sometimes known as self-locking nuts, contain a plastic insert that deforms to the thread of the fastener and prevents loosening without the aid lock threading adhesive.They are commonly used in applications where a secure fastening is required or when joining soft materials such as wood and plastics where high surface pressure might damage the material, or when there is a short clamp load. However, their principal advantage is in applications where there is a high degree of vibration. Locking nuts resist loosening over time in dynamic load conditions and because of this, they are often used in:

• Domestic appliances such as washers and dryers


• Industrial machinery


• Automotive industry

RS PRO is the own brand of RS. The RS PRO Seal of Approval is your assurance of professional quality, a guarantee that every part is rigorously tested, inspected, and audited against demanding standards. Making RS PRO the Smart Choice for our customers.

Small Pack Size: 1224373
Large Pack Size: 2646422