Value Collection MSFI0-400250-100BX 4-40 Flat Head Slotted Machine

Product Description

The VALUE COLLECTION MSFI0-400250-100BX is a 4-40 x 1/4-inch flat head slotted machine screw sold in a box of 100. It is manufactured from Grade 2 steel with a zinc plating finish that provides basic corrosion resistance in dry indoor environments. The flat head profile sits flush with the mating surface when driven into a countersunk hole, making it well-suited for assemblies where a low-profile or flush surface is required. The slotted drive accepts a standard flat-blade screwdriver. These screws use Unified National Coarse (UNC) thread form and are sized for 4-40 threaded holes or nuts. Licensed electricians, HVAC technicians, and general maintenance professionals commonly use 4-40 hardware in panel assembly, equipment enclosures, and light-duty mechanical fastening applications.

These screws are appropriate for light-duty fastening tasks in residential and commercial equipment, electronics enclosures, control panels, and small mechanical assemblies. The 4-40 thread size is a standard designation in inch-series hardware and is widely encountered in electrical and HVAC control components. Overall length is 1/4 inch, and the length under head is also 1/4 inch, consistent with flat head geometry where the head tapers flush. The box quantity of 100 units supports service stock, shop inventory, and repeat-use fastening work where having a reliable supply on hand reduces downtime.

Key Features

• 4-40 UNC thread form for compatibility with standard inch-series tapped holes and nuts
• Flat head profile designed to sit flush in countersunk mounting surfaces
• Slotted drive accepts flat-blade screwdrivers for straightforward installation
• Grade 2 steel construction balances adequate tensile strength with cost efficiency for light-duty use
• Zinc plating provides basic corrosion protection in dry indoor service environments
• Box of 100 units supports ongoing shop and service inventory needs

Compatibility

Designed as a standard inch-series machine screw for use in any application requiring a 4-40 UNC threaded fastener with a flush flat head profile.

Installation Notes

Installation requires a flat-blade screwdriver sized to the slotted head. A countersink must be present in the mating material to achieve a flush seating surface with a flat head screw. Always power down and de-energize any electrical or HVAC equipment before replacing or installing fasteners in live panels or enclosures. Do not exceed the load ratings appropriate for Grade 2 steel hardware in structural or high-vibration applications.