National Marker N222125 Zinc Round U Bolt 5/16 in

Product Description

The NATIONAL MARKER N222125 is a zinc-plated round U bolt designed for hanging and fastening applications across pipe, wood, and structural supports. Built to catalog model 2190 series specifications, this U bolt measures 5/16 inch in thread diameter, 1-3/8 inches in inside width, and 2-1/2 inches in inside height. Plate and hex nuts are included in the package. The steel construction with zinc plating provides corrosion resistance suitable for both indoor and outdoor service environments. At 0.147 pounds per unit, it is a lightweight, single-piece fastener ready for immediate installation.

This U bolt is suited for residential and light industrial applications including plumbing, automotive, and general mechanical assembly. The pipe sizes listed for this fastener refer to the inside diameter of standard pipe, making it straightforward to match to the correct pipe size on the job. It is well-suited for HVAC, plumbing, and mechanical contractors who need a reliable pipe-hanging or conduit-securing fastener in standard sizes. Minimum purchase quantity is 5 units per order.

Key Features

• Zinc-plated steel construction for corrosion resistance in wet and dry environments
• Round U bolt profile sized for standard pipe inside diameters
• Plate and hex nuts included — no additional hardware required
• Suitable for automotive, plumbing, and general industrial fastening
• Lightweight at 0.147 pounds per unit for easy handling and installation
• Part of the National catalog model 2190 series for consistent replacement sourcing

Compatibility

Designed as an OEM-style replacement and general-purpose fastener compatible with standard pipe applications where a round U bolt with 5/16 inch thread diameter is specified. Pipe size compatibility is based on standard pipe inside diameter dimensions.

Installation Notes

Installation is typically performed by plumbers, HVAC technicians, or mechanical contractors during pipe-hanging or support-anchoring work. Ensure the mating pipe or substrate is clean and properly supported before securing the U bolt. Tighten hex nuts evenly to avoid distorting the bolt bend or damaging pipe walls. Follow applicable local mechanical codes for pipe support spacing and fastener requirements.

Technical Specifications

• Thread Diameter: 5/16 inches
• Inside Width: 1-3/8 inches
• Inside Height: 2-1/2 inches
• Material: Steel with zinc plating
• Weight: 0.147 pounds
• Hardware Included: Plate and hex nuts
• Catalog Series: 2190
• Unit of Measure: Each
• Minimum Order Quantity: 5

Standard Information

• Brand: NATIONAL MARKER
• Manufacturer Part Number: N222125