Irwin 21 Locking C-clamp 18 Inches Regular Tips

Product Description

The IRWIN 21 is a heavy-duty locking C-clamp designed for clamping, welding, and fabrication work across a wide range of trade applications. Built from alloy steel, this clamp features a wide-opening jaw that accommodates a variety of workpiece shapes and sizes. The jaw opens to 18 inches, making it well suited for large-scale clamping tasks where standard C-clamps fall short. Regular tips provide direct, stable contact on flat and moderately curved surfaces. Locking action holds the set position without continuous hand pressure, freeing the technician to work with both hands. This clamp is a standard tool for ironworkers, pipefitters, welders, and general contractors.

The IRWIN 21 locking C-clamp is used in residential and commercial construction, metal fabrication shops, and mechanical service environments. It is commonly applied when holding structural members, pipe, sheet metal, or formed stock during tack welding, drilling, or assembly. The 18-inch jaw capacity handles oversized workpieces that smaller locking clamps cannot reach. Regular tips are appropriate for jobs where broad, even clamping pressure on accessible flat surfaces is required.

Key Features

• 18-inch jaw opening provides wide clamping capacity for large workpieces
• Alloy steel construction for durability in demanding trade environments
• Locking C-clamp design holds set position hands-free
• Regular tips deliver stable, even contact on flat and gently curved surfaces
• Wide-opening jaw increases versatility across varied clamping shapes

Compatibility

Designed as an OEM-style locking C-clamp for general-purpose clamping, welding, and fabrication tasks requiring an 18-inch jaw capacity.

Installation Notes

Locking C-clamps are typically set by hand by tradespeople including welders, pipefitters, and ironworkers. Adjust the jaw screw to the approximate workpiece thickness before locking to avoid overloading the clamp mechanism. Always inspect the clamp body and screw threads for wear or damage before applying high clamping force. Follow applicable worksite safety and hand-tool guidelines when using clamps near welding operations or energized equipment.

Technical Specifications

• Jaw Opening: 18 inches
• Material: Alloy Steel
• Clamp Type: Locking C-Clamp
• Tip Style: Regular Tips
• Weight: 2.71 pounds
• UPC: 038548000213

Standard Information

• Brand: IRWIN
• Manufacturer Part Number: 21