Proto J404A C-clamp 4 in 6500 Lb Steel Black Oxide

Product Description

The PROTO J404A is a heavy-duty C-clamp built for demanding trade and industrial applications. It features a maximum opening capacity of 4 inches and a throat depth of 2.75 inches, making it well-suited for gripping thick workpieces or assemblies. The clamp is rated to a load capacity of 6,500 pounds, providing substantial clamping force for metalworking, fabrication, and maintenance tasks. The body, spindle, and anvil are all constructed from steel with a black oxide finish. A smooth swivel pad on the anvil face distributes clamping pressure evenly across the workpiece surface. This clamp is a standard tool for electricians, pipefitters, ironworkers, and general trade professionals who need reliable, high-force clamping on the job.

The PROTO J404A is appropriate for use in both residential and commercial settings wherever secure mechanical clamping is required. Typical applications include holding pipe, conduit, structural steel, or fabricated assemblies during welding, drilling, or installation work. The 4-inch opening accommodates a wide range of material thicknesses, and the 2.75-inch throat depth allows reach over flanges or edges without repositioning. Trade professionals in HVAC, electrical, and plumbing disciplines regularly use C-clamps of this type when securing brackets, mounting hardware, or positioning components during rough-in and finish work.

Key Features

• 4-inch maximum opening capacity handles thick workpieces and stacked materials
• 6,500 lb rated load capacity for high-force clamping applications
• 2.75-inch throat depth provides clearance over flanges and edges
• All-steel construction: body, spindle, and anvil for durability under load
• Black oxide finish for corrosion resistance in shop and field environments
• Smooth swivel pad distributes clamping pressure evenly across the contact surface

Compatibility

Designed as a standard C-clamp for general trade and industrial use where a 4-inch opening and 6,500 lb load capacity are required.

Installation Notes

No power source or shutoff is required for mechanical clamp use. Inspect the clamp body, spindle threads, and swivel pad before each use and do not use a clamp that shows cracks, deformation, or stripped threads. Do not exceed the rated load capacity of 6,500 pounds. Apply clamping force gradually and ensure the workpiece is fully seated against the anvil before loading.