Value Collection 3128MST Truss Head Slotted Machine Screw

Product Description

The VALUE COLLECTION 3128MST is a truss head slotted machine screw designed for general-purpose fastening applications across a wide range of trade and industrial settings. Manufactured from steel with a zinc finish, this screw features a 5/16-18 unified coarse thread and measures 1.75 inches in length under the head. The broad, low-profile truss head distributes clamping load over a wider surface area, making it well suited for softer materials or thin panels where a standard pan or hex head might pull through. Compliance with ASME B18.6.3 and SAE J82 confirms dimensional and mechanical consistency. Electricians, HVAC technicians, plumbers, and general contractors commonly keep this fastener size on hand for panel work, bracket mounting, and equipment assembly.

This screw is appropriate for residential and light commercial applications wherever a 5/16-18 coarse-thread fastener with a slotted truss head is specified. Typical use cases include securing electrical enclosure covers, HVAC unit panels, junction boxes, and sheet metal brackets. The zinc finish provides basic corrosion resistance suitable for indoor and dry-location installations. It is sold individually but carries a minimum order quantity of 50 units, making it practical for stocking in service vehicles or shop inventory.

Key Features

• Truss head profile distributes load over a wider bearing surface than standard pan or round heads
• 5/16-18 unified coarse thread for fast engagement in tapped holes and standard fastener hardware
• Slotted drive compatible with flat-blade screwdrivers and power drivers with slotted bits
• Zinc finish provides basic corrosion protection for indoor and dry-location use
• Meets ASME B18.6.3 and SAE J82 dimensional and material standards
• Steel construction for reliable tensile and shear strength in light structural and panel fastening

Compatibility

Designed as a standard 5/16-18 coarse-thread truss head machine screw per ASME B18.6.3 and SAE J82, suitable for use in any tapped hole or threaded insert accepting a 5/16-18 thread pitch.

Installation Notes

Installation requires a flat-blade screwdriver or a slotted power-driver bit sized for the 5/16-18 drive recess. De-energize any electrical equipment and follow applicable NEC or equipment manufacturer lockout/tagout procedures before replacing or installing fasteners on live panels or enclosures. Do not over-torque slotted drive fasteners, as the drive recess is more susceptible to cam-out than hex or Torx drives. Verify thread engagement depth in the mating material meets the specifications required for the load being applied.