Value Collection 521 Machine Screws

Product Description

The VALUE COLLECTION 521 is a machine screw intended for general fastening applications across mechanical, electrical, and light structural assemblies. Machine screws are threaded fasteners designed to mate with a pre-tapped hole or a nut, securing two or more components together with a consistent clamping force. These screws are a staple in trade work wherever a removable, reliable threaded connection is needed. Installers across HVAC, electrical, plumbing, and general mechanical service encounter machine screws daily in panel assemblies, junction boxes, equipment housings, and component mounting applications.

Machine screws in this category are suited for both residential and commercial service environments. They are commonly used when mounting controls, securing access panels, fastening terminal blocks, or assembling equipment sub-components. The 521 is sold in minimum order quantities of 100 units per order, making it practical for service shops and contractors stocking their bins for recurring fastener needs.

Key Features

• Standard machine screw form factor compatible with tapped holes and nuts
• Minimum order quantity of 100 units supports bulk stocking for service operations
• Lightweight individual unit weight suitable for high-volume fastener applications
• Applicable across a wide range of trade assembly and equipment service tasks

Compatibility

Designed as a general-purpose machine screw replacement or stock fastener for use in mechanical assemblies, electrical enclosures, and equipment panels where a standard threaded fastener is specified.

Installation Notes

Machine screws should be installed by qualified tradespeople following applicable codes such as the NEC for electrical assemblies or IFGC for gas equipment panels. Always de-energize electrical equipment and relieve system pressure before removing or replacing fasteners in live assemblies. Use the correct driver type and size to avoid cam-out or fastener damage. Do not overtighten into tapped holes, particularly in thin sheet metal or plastic housings.