Metallics Machine Screw 1/4-20 x 3" Round Head Combo Drive Steel Zinc

Metallics Industries Machine Screw 1/4-20 x 3" Round Head Combo Drive Steel Zinc

Professional Fastener Solution with Dual Drive System

The Metallics Industries Machine Screw 1/4-20 x 3" Round Head Combo Drive delivers exceptional performance and reliability for electrical, plumbing, and HVAC applications. This steel zinc machine screw provides dependable fastening solutions designed for professional contractors, electricians, and industrial technicians, offering the proven quality and precision engineering that professionals trust from a leading manufacturer of electrical hardware and industrial fasteners.

Professional Features & Benefits

Dual Drive Performance

• Combo Slotted/Phillips Drive System - Two drives in one head providing installation flexibility with both slotted and Phillips drivers for maximum versatility
• 1/4-20 Thread Specification - Precision 20 threads per inch for secure engagement and reliable holding power in threaded applications
• 3" Length Design - Extended length provides superior fastening capability for thick materials and deep installations
• Round Head Configuration - Professional round head design with 0.443-0.472" width for optimal bearing surface and finished appearance

Material & Construction Excellence

• Steel Zinc Construction - AISI 1006-1022 steel with zinc finish provides corrosion resistance and durability for demanding applications
• Rockwell B70-B100 Hardness - Professional hardness rating ensures reliable performance and resistance to stripping during installation
• 60,000 PSI Minimum Tensile Strength - High tensile strength rating provides exceptional holding power for critical fastening applications

Professional Installation Features

• Precision Threading - Machine thread design ensures smooth engagement with threaded holes and nuts for professional installations
• Driver Size #3 Compatibility - Standard #3 driver size works with common professional tools and driver bits

Technical Specifications

Thread: 1/4-20 (20 threads per inch), Length: 3 inches, Head Type: Round, Drive Type: Slotted/Phillips Combo, Material: Steel Zinc (AISI 1006-1022), Finish: Zinc, Head Width: 0.443-0.472 inches, Head Height: 0.16-0.175 inches, Driver Size: #3, Hardness: Rockwell B70-B100, Tensile Strength: 60,000 PSI minimum, Phillips Recess Depth: 0.121-0.147 inches, Slot Depth: 0.082-0.109 inches, Slot Width: 0.064-0.075 inches, Pack Type: Jar, Weight: 3.58 lbs

Installation & Usage

1. Select appropriate threaded hole or nut matching 1/4-20 thread specification
2. Choose either slotted or Phillips driver based on installation requirements and tool availability
3. Align machine screw with threaded opening ensuring proper thread engagement
4. Begin threading by hand to prevent cross-threading and ensure proper alignment
5. Use appropriate driver to tighten screw, applying consistent torque for secure fastening
6. Verify proper seating of round head against mounting surface for optimal load distribution

Professional Applications

Ideal for:

• Electrical Panel Assembly - Securing components, mounting hardware, and electrical enclosure assembly
• HVAC System Installation - Fastening ductwork components, mounting brackets, and system hardware
• Plumbing Applications - Securing pipe supports, mounting fixtures, and plumbing system components
• Industrial Equipment Assembly - Machine assembly, equipment mounting, and industrial hardware applications
• Control Panel Construction - Mounting switches, controls, and electrical components in panel boxes
• Mechanical Assembly - General mechanical fastening where threaded connections are required
• Maintenance and Repair - Replacement fasteners for equipment servicing and facility maintenance
• Commercial Construction - Building systems installation and commercial hardware mounting applications

Steel Zinc Construction Advantage

The steel zinc construction provides excellent corrosion resistance while maintaining the strength and durability required for professional applications. The zinc finish offers protection against environmental factors while the steel core ensures reliable tensile strength and threading performance. This combination makes these machine screws ideal for both indoor and outdoor installations where corrosion resistance and mechanical strength are essential.

Why Choose Metallics Industries Quality?

Metallics Industries has been a pioneer in combo drive fastener technology since 1985, being the first fastener company in America to offer a full line of combo drive screws. Our commitment to precision manufacturing ensures consistent thread quality, accurate dimensions, and reliable performance. Each machine screw undergoes comprehensive quality testing to meet professional standards for electrical, plumbing, HVAC, and construction applications. Trust Metallics Industries for dependable fastening solutions that deliver the performance and reliability that professional contractors and industrial technicians demand.