Minerallac Company 21040 - Machine screws for use with a pre-tapped hole or with a nut. They are made of steel with a zinc plated finish and a silver flat head. The screws are 1/4"-20 size and 2-1/2" long, with a square drive and #3 driver size.
Minerallac Company

21040

Alternate Item Number: 12113359

UPC: 085937210401

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Minimum Qty: 100

Multiplier: 100

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Overview

The Minerallac Company 21040 is a 1/4-20 x 2-1/2 inch machine screw, meticulously crafted from zinc-plated steel for superior corrosion resistance. This fastener features a flat head design, ideal for achieving a flush finish when installed in countersunk holes, and a square drive that ensures excellent torque transfer, significantly minimizing cam-out during assembly. The robust zinc plating provides a protective barrier against rust and environmental degradation, making the 21040 suitable for a variety of indoor and protected outdoor industrial applications where secure and reliable fastening is paramount. Its precise dimensions and durable construction make it a dependable choice for demanding assembly tasks. SKU: 21040. Country of Origin: US. UNSPSC Code: 31160000. This specific machine screw is identified by its 1/4-20 thread size and a length of 2-1/2 inches. The flat head configuration is designed for applications requiring a smooth, unobtrusive surface after installation, particularly when seated in a countersunk recess. The square drive mechanism is engineered to accept a corresponding square bit, facilitating efficient and secure tightening with reduced slippage compared to other drive types. The zinc plating offers a standard level of protection against oxidation and corrosion, extending the service life of the fastener in typical industrial environments.
  • Material: Zinc-plated Steel
  • Size: 1/4-20 x 2-1/2 inch
  • Head Type: Flat Head (FH)
  • Drive Type: Square Drive (SQ DR)
  • Corrosion Resistance: Zinc Plating (ZP)

Specifications

Application
For use with a pre-tapped hole or with a nut.
Drive Type
Square Drive
Drive Type
Square;Square Drive
Driver Size
#3
Finish
Zinc Plated
Head Color
Silver
Head Diameter
0.477 in
Head Diameter
12.1158 mm
Head Height
0.153 in
Head Height
3.8862 mm
Head Type
Flat Head
Length
2-1/2 in
Material
Steel
Size
1/4"-20
Thread Size
20
Thread Type
2A External Threads
Type
Machine Screw
Package Weight (Imperial)
3 lbs
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Frequently Asked Questions about Minerallac Company

What are the main product lines offered by Minerallac Company?

Minerallac Company offers multiple comprehensive product lines including Minerallac Traditional (electrical fasteners), Strut Fittings, Stainless Steel Fasteners, Black Claw, Impact Staples, and Redmore. Their Traditional line features over a thousand electrical fastener variations covering conduit/cable/wire products, nail straps, beam clamps, metal stud & drywall accessories, acoustical supports, voice/data hardware, and miscellaneous electrical installation components.

What is Minerallac Company's warranty policy?

Minerallac Company provides a limited warranty that guarantees all products are free from defects in material and workmanship. If a product fails to meet this warranty, Minerallac's sole liability is to replace the product at no charge. The warranty is exclusive and does not cover consequential damages, lost profits, or implied warranties of merchantability or fitness for a particular purpose.

What industries and applications are Minerallac Company products used for?

Minerallac Company products are used extensively across electrical, construction, and industrial applications, including conduit and cable support, beam mounting, metal stud and drywall installation, voice/data infrastructure, and low voltage systems. Their product lines cover critical fastening solutions for electrical contractors, with specialized offerings in conduit hangers, straps, beam clamps, cable supports, and mounting hardware for various industrial environments.

What technical support does Minerallac Company offer?

Minerallac Company offers comprehensive technical support through multiple channels, including a toll-free customer service line at 800-927-3293, email support at [email protected], and online resources at www.minerallac.com. Their support covers product selection, technical specifications, and customer service for their extensive line of electrical fasteners, hangers, straps, and hardware across multiple product brands including Minerallac Traditional, Cully, Black Claw, IMPACT Staples, and Minerallac Stainless Steel. Support hours are 8:00 A.M. to 5:00 P.M. CT for their corporate office and 8:00 A.M. to 5:00 P.M. PT for their regional office.

What are the key features of Minerallac Company products?

Minerallac Company products feature a comprehensive range of electrical fasteners and hardware with exceptional versatility, including over 1,000 different sizes, styles, and finishes. Key features include multiple product lines such as Traditional, Strut Fittings, and Stainless Steel options with specialized finishes like 304/316 Stainless Steel, Hot-Dipped Galvanized, and Zinc Electroplate. Their products are engineered for electrical contractors, offering time-saving solutions with high-quality fasteners designed for durability, corrosion resistance, and worker safety across various installation environments.

What environmental ratings do Minerallac Company products have?

Minerallac Company products have robust environmental ratings, including UL 508A Type 1, 2, 3, 4, 4X, 12, and 13 certifications, CSA Type 1-4X, 12, and 13 ratings, and IEC 60529 IP66 protection. The products are WEEE and RoHS compliant, with UV and oil resistance, and can operate in extreme temperatures ranging from -55°C to 105°C, making them suitable for harsh industrial environments.

What accessories are available for Minerallac Company products?

Minerallac Company offers a comprehensive range of accessories across multiple product categories, including hardware, fasteners, and mounting solutions. Key accessories include stove bolts with nuts, wing nut washers, bar joist washers, stud clip adapters, brackets, perforated strapping, cable support options like J-hooks and bridle rings, box mounting brackets, outlet retainers, and various stud and drywall supports. Their accessories are available in multiple finishes such as stainless steel, hot-dipped galvanized, zinc electroplate, and powder-coated options.

How are Minerallac Company products typically installed?

Minerallac Company products are typically installed using a variety of specialized fastening solutions, including conduit hangers, straps, beam clamps, and mounting brackets designed for different electrical and construction applications. Installation methods vary by product type, with options for metal studs, drywall, beams, acoustical surfaces, and low voltage systems. The company offers multiple installation styles such as one-hole and two-hole straps, universal beam clamps, and specific mounting hardware to ensure secure and efficient attachment across diverse electrical and construction environments.

What communication protocols do Minerallac Company products support?

Minerallac Company's Brad product line supports multiple industrial communication protocols, including Ethernet, DeviceNet, PROFIBUS, Modbus, CANopen, Serial, AS-interface, and CC-Link. Their comprehensive portfolio covers over 40 industrial protocols, providing flexible communication solutions for various industrial automation applications from PC-based control to PLC systems.