Authorized Minerallac Company Distributor
Minerallac Company 40631J - This is a 3/8 inch external tooth lock washer. It is zinc plated and supplied in a jar. The sheet identifies it as a lock washer for fastening applications.
Minerallac Company

40631J

Alternate Item Number: 16733982

UPC: 085937053930


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Minimum Qty: 100

Multiplier: 100

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Overview

The Minerallac Company 3/8" External Tooth Lock Washer (SKU 40631J) is a precision-engineered fastening solution designed to prevent loosening in high-vibration industrial applications. Manufactured from durable zinc-plated steel, this external tooth lock washer features a 3/8" nominal size with serrated external teeth that bite into mating surfaces to create a secure, vibration-resistant joint. The zinc plating provides corrosion resistance, extending service life in harsh environments while maintaining consistent clamping force. Supplied in a 100-piece jar for bulk handling, this lock washer is ideal for applications requiring reliable torque retention, such as heavy machinery, automotive assembly, construction equipment, and industrial panel fabrication. Unlike standard flat washers, the external teeth of this component dig into both the fastener head and the assembly surface, resisting rotational forces that cause typical loosening. The 3/8" size matches common bolt diameters, making it a direct replacement for standard external tooth lock washers in existing assemblies. Its simple design eliminates the need for additional locking mechanisms, reducing assembly time and cost while improving joint integrity. This lock washer is a cost-effective solution for maintaining fastener tension in critical connections where joint failure could compromise safety or performance.
  • 3/8" nominal size for standard bolt compatibility
  • External serrated teeth for superior vibration resistance
  • Zinc-plated steel construction for corrosion protection
  • 100-piece jar packaging for bulk handling efficiency
  • Prevents loosening in high-torque, high-vibration applications

Specifications

Color
Zinc Plated
Material
Steel
Material
Zinc-Plated Steel
Size
3/8"
Size
3/8 Inch
M4 (0.7) x 16mm Metric Flat Head Phillips Din 965 Machine Screw Steel Zinc

JLWX8SB

M4 (0.7) x 16mm Metric Flat Head Phillips Din 965 Machine Screw Steel Zinc
A hardened circular washer with twisted prongs or teeth extending from the outer edge. It is made of steel with a zinc plated finish. The fastener size is #10.

40616

A hardened circular washer with twisted prongs or teeth extending from the outer edge. It is made of steel with a zinc plated finish. The fastener size is #10.
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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.