J.w. Winco 913.3-M4-8-KU Set Screw M4 X 0.70 X 8 Mm

Product Description

The J.W. WINCO 913.3-M4-8-KU is a metric hex-drive set screw designed for secure, non-permanent fastening in mechanical assemblies. Built from Grade 5.8 steel with a black oxide finish, it features an M4 x 0.70 thread and an 8 mm thread length. The nylon soft tip protects shaft surfaces from marring or scoring, making this fastener a reliable choice for holding collars, pulleys, and similar components in position without damaging the mating surface. A 2 mm hex key drives the screw. Licensed HVAC, plumbing, and mechanical trade professionals and assembly technicians will find this fastener suited to precision-fit applications where surface protection is required.

This set screw is intended for use in general mechanical and industrial assemblies where a metric M4 thread is specified. The soft nylon tip makes it appropriate for applications involving hardened or finished shafts where point-contact damage must be avoided. Typical installations include shaft collars, set-collar positioning, rotary components, and light-duty locking in equipment such as pumps, fan assemblies, and motor-driven hardware common in HVAC and plumbing systems.

Key Features

• M4 x 0.70 metric thread for standard metric fastening applications
• Nylon soft tip protects mating shaft surfaces from scoring or marring
• Grade 5.8 steel construction for reliable clamping strength
• Black oxide finish provides mild corrosion resistance and reduces light reflection
• Hex socket drive accepts a 2 mm hex key (0.0787 inch)
• 8 mm full thread length for positive thread engagement

Compatibility

Designed as an OEM-style metric set screw for mechanical assemblies requiring an M4 x 0.70 hex-drive soft-tip fastener with an 8 mm thread length.

Installation Notes

Install using a 2 mm hex key; ensure the mating threaded hole is clean and free of debris before driving the screw. De-energize and lock out any rotating equipment before servicing fasteners on motor shafts, pulleys, or fan assemblies. Do not overtighten - the nylon tip is designed for controlled clamping force, not high-torque seating. Follow applicable equipment manufacturer specifications for final seating depth and holding force.