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Minerallac Company 55540J - This is a carriage bolt with a round head and square neck design. It is made of steel with a zinc plated finish. The bolt size is 3/8-16 x 2-1/2 in, with a 3/8 in diameter and 2.500 in length.
Minerallac Company

55540J

Alternate Item Number: 12112143

UPC: 085937042910

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Minimum Qty: 50

Multiplier: 50

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Overview

The Minerallac 55540J is a 3/8-16 x 2-1/2 inch Grade 2 carriage bolt with a fully threaded shank. Manufactured by Minerallac Company, a US-based fastener specialist since 1927, this zinc-plated bolt features a smooth domed head and square neck to prevent rotation during installation. Designed for wood-to-metal or metal-to-metal connections, it is supplied in 50-unit gravity-feed jars (300 units per master carton). The zinc plating provides basic corrosion resistance for indoor and protected outdoor applications. This Grade 2 bolt meets A307 standards and is suitable for general construction, maintenance, and light industrial assemblies where a flush-mounted, non-protruding head is required.
  • 3/8-16 thread size, 2-1/2" length
  • Fully threaded shank for maximum grip
  • Zinc-plated for basic corrosion resistance
  • Smooth domed head with square neck to prevent rotation
  • Grade 2/A307 specification, meets standard industrial requirements

Specifications

Application
The square neck is designed to keep the bolt from turning as a nut is thightened.
Diameter
3/8 in
Finish
Zinc Plated
Head Type
Round Head
Head Type
Rounded Head
Length
2.5 in
Length
63.5 mm
Material
Zinc
Material
Zinc-Plated Steel
Material
Steel
Size
3/8-16 x 2-1/2"
Thread
16
Thread Type
16 TPI
Type
Carriage Bolts
Package Weight (Imperial)
3.975 lbs
Carriage bolts with a round head and zinc plated finish. Made of steel and sized 3/8-16 x 1-1/4 in. The sheet notes a square neck designed to keep the bolt from turning as a nut is tightened.

55520

Carriage bolts with a round head and zinc plated finish. Made of steel and sized 3/8-16 x 1-1/4 in. The sheet notes a square neck designed to keep the bolt from turning as a nut is tightened.
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JCB33G

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Round head carriage bolt with a square neck under the head and a unified thread pitch. It is made of steel with a zinc plated finish. The bolt is 1/4-20 x 1-1/4 in, with a 1/4 in diameter and 1.250 in length.

55120

Round head carriage bolt with a square neck under the head and a unified thread pitch. It is made of steel with a zinc plated finish. The bolt is 1/4-20 x 1-1/4 in, with a 1/4 in diameter and 1.250 in length.
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55156

Carriage bolts with a round head and zinc plated finish. Made of steel and sized 1/4"-20 x 3-1/2" with a 1/4" diameter and 20 threads. The square neck is designed to keep the bolt from turning as a nut is tightened.
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55164

Carriage bolts with a round head and zinc plated finish. They are made of steel and sized 1/4"-20 x 4" with a 1/4" diameter and 20 threads. The square neck is designed to keep the bolt from turning as a nut is tightened.
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55324

Carriage bolts with a round head and square neck designed to keep the bolt from turning as a nut is tightened. Made of steel with a zinc plated finish. Size is 5/16-18 x 1-1/2 in., with a 5/16 in. diameter and 1.500 in. length.
These are carriage bolts with a round head and zinc plated finish. They are made of steel and sized 5/16-18 x 1 in, with a 5/16 in diameter and 18 threads. The square neck is designed to keep the bolt from turning as a nut is tightened.

55316

These are carriage bolts with a round head and zinc plated finish. They are made of steel and sized 5/16-18 x 1 in, with a 5/16 in diameter and 18 threads. The square neck is designed to keep the bolt from turning as a nut is tightened.
Round head carriage bolt with a square neck under the head and a unified thread pitch. It is made of steel with a zinc plated finish. The bolt is 1/4 in diameter and 3/4 in long, with 20 TPI threads.

55112

Round head carriage bolt with a square neck under the head and a unified thread pitch. It is made of steel with a zinc plated finish. The bolt is 1/4 in diameter and 3/4 in long, with 20 TPI threads.

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.