National Marker N222133 Zinc Round U-bolt Pipe Fastener

Product Description

The NATIONAL MARKER N222133 is a zinc-plated round U-bolt designed for hanging and fastening applications across pipe, wood, and structural supports. Part of the National catalog 2190 series, this U-bolt measures 5/16 inches in thread diameter with a 1-3/8 inch inside width and 3-3/4 inch leg length. Constructed from steel with a zinc finish for corrosion resistance, it ships with plate and hex nuts included. At 0.193 pounds, it is a compact, lightweight fastener suited for both residential and light industrial work. Licensed trade professionals and experienced DIYers install these in plumbing, automotive, and general mechanical applications.

The N222133 U-bolt is used in a wide range of fastening scenarios where pipe, conduit, or round stock must be secured to a mounting surface. The pipe sizes referenced in manufacturer specifications reflect inside diameters of standard pipe, making it straightforward to match to common plumbing and mechanical pipe runs. Typical install environments include residential plumbing lines, automotive exhaust and fuel line mounting, and general industrial bracketing where a round-profile clamp is required.

Key Features

• Zinc-plated steel construction for corrosion resistance in indoor and moderate-duty environments
• 5/16 inch thread diameter provides secure clamping force for light-to-medium pipe fastening
• Plate and hex nuts included — no additional hardware required for standard installation
• Round bend profile suits standard round pipe and conduit profiles
• Suitable for automotive, plumbing, and general industrial fastening applications
• Pipe size references reflect inside diameters of standard pipe for accurate sizing

Compatibility

Designed as a standard-profile round U-bolt for securing pipe, conduit, or round structural members to wood, metal, or other mounting substrates in residential, automotive, and light industrial applications.

Installation Notes

Installation is typically performed by plumbers, automotive technicians, or general mechanical tradespeople using standard hand tools. Before installation on any active pipe or pressurized line, shut off and depressurize the system per applicable codes. Tighten hex nuts evenly to avoid cocking the U-bolt on the pipe, but do not overtighten, as this can deform thin-wall pipe or strip the threads. Follow applicable IPC or local mechanical codes when securing supply or drain lines.

Technical Specifications

• Thread Diameter: 5/16 inches
• Inside Width: 1-3/8 inches
• Leg Length: 3-3/4 inches
• Material: Steel
• Finish: Zinc plated
• Included Hardware: Plate and hex nuts
• Weight: 0.193 pounds
• Unit of Measure: Each
• UPC: 00038613125902

Standard Information

• Brand: NATIONAL MARKER
• Manufacturer Part Number: N222133