1. Introduction
Thank you for choosing the MAXPOWER 12 Inch Adjustable Offset Hex Wrench. This manual provides essential information for the safe and effective use, maintenance, and care of your new tool. Please read these instructions thoroughly before operation and retain them for future reference.
2. Product Overview
2.1 Product Features
- Capacity: 12 Inch adjustable hex wrench designed to fit pipe nuts with a capacity of 1-1/8" (29 mm) to 2-5/8" (67 mm).
- Secured Grip: Hex jaw design provides a secure grip on multi-sided square nuts, hex nuts, unions, and valve nuts.
- Thin and Smooth Jaws: Jaws are engineered to slide into tight and restricted spaces, enhancing efficiency.
- Durability: Features drop-forged and heat-treated Cr-Mo jaws (HRC 40-49), a durable ductile cast iron body, and a powder-painted anti-rust surface.
- Application Range: Ideal for securing drain nuts on sinks and tubs, suitable for both professional plumbers and homeowners.
2.2 Components
Familiarize yourself with the main components of your MAXPOWER Adjustable Offset Hex Wrench:

Image: The MAXPOWER 12 Inch Adjustable Offset Hex Wrench, showcasing its red cast iron body and black hex jaws.

Image: Diagram illustrating the dimensions of the 12-inch wrench, including its 1-1/8" (29mm) to 2-5/8" (67mm) jaw capacity.

Image: Close-up view of the wrench with labels pointing to the Cr-Mo Jaw, self-cleaning threads, non-stick adjustable nut, and durable ductile cast iron body.

Image: The wrench disassembled, showing the main body, the movable jaw with its threaded shaft, and the adjustment nut as separate parts.
3. Setup
3.1 Initial Inspection
Upon receiving your wrench, inspect it for any signs of damage or manufacturing defects. Ensure all components are present and functioning correctly. The wrench should operate smoothly without excessive play.
3.2 Adjusting the Jaw
The wrench features an adjustable jaw mechanism. To adjust the jaw opening:
- Locate the adjustment nut positioned below the movable jaw.
- Rotate the adjustment nut to widen or narrow the jaw opening. Turn clockwise to close the jaws and counter-clockwise to open them.
- Ensure the jaws are set to the appropriate size for the fastener or pipe you intend to grip, allowing for a secure fit without excessive force.

Image: A detailed view of the wrench's adjustment nut and threaded shaft, with an arrow indicating the rotational movement for opening and closing the jaws.
4. Operating Instructions
4.1 General Use
The MAXPOWER Adjustable Offset Hex Wrench is designed for gripping and turning various fasteners, particularly those with hex or square profiles, and pipes in confined spaces.
- Select Correct Size: Adjust the jaw opening to slightly larger than the fastener or pipe you are working with.
- Position Wrench: Place the wrench jaws around the fastener or pipe. The offset design allows for better access in tight areas.
- Tighten Grip: Rotate the adjustment nut until the jaws firmly grip the object. Ensure the hex jaws engage multiple sides of the fastener for maximum grip.
- Apply Force: Apply steady, controlled force to the handle to turn the fastener or pipe. Avoid sudden jerking motions.
- Reposition if Necessary: For continuous turning, release pressure, reposition the wrench, and re-engage the grip.
4.2 Securing Different Fastener Types
The hex jaw design is optimized for:
- Hex Nuts: The jaws will naturally conform to the hexagonal shape, providing a strong, non-slip grip.
- Square Nuts: Similar to hex nuts, the multi-sided engagement ensures a secure hold.
- Unions and Valve Nuts: The thin jaws and wide opening are particularly useful for these applications, especially in plumbing.

Image: A collage showing the MAXPOWER wrench being used in four different scenarios, demonstrating its versatility on various pipes and fasteners in plumbing and industrial settings.

Image: A person wearing gloves using the MAXPOWER wrench to tighten or loosen a large nut on a red pipe, highlighting the tool's ergonomic handling and grip.
4.3 Safety Precautions
- Always wear appropriate personal protective equipment, such as safety glasses and gloves.
- Ensure the wrench jaws are clean and free of grease or debris to maintain a secure grip.
- Do not use the wrench if it is damaged or shows signs of wear.
- Never use a pipe to extend the handle for additional leverage, as this can damage the tool or cause injury.
- Keep hands and fingers clear of the jaws during adjustment and operation.
- Store the wrench in a dry, secure place away from children.
5. Maintenance
5.1 Cleaning
After each use, wipe down the wrench with a clean, dry cloth to remove dirt, grease, and moisture. For stubborn grime, a mild detergent and water can be used, followed by thorough drying.
5.2 Lubrication
Periodically apply a light coat of machine oil to the adjustment screw and movable jaw mechanism to ensure smooth operation and prevent rust. Wipe off any excess oil.
5.3 Storage
Store the wrench in a dry environment to prevent corrosion. Keeping it in a tool bag or on a tool rack will protect it from damage and keep it readily accessible.
5.4 Inspection
Regularly inspect the jaws for wear, cracks, or damage. Check the adjustment mechanism for smooth movement and ensure the handle is free from cracks or bends. Replace the tool if any significant damage is observed.
6. Troubleshooting
This section addresses common issues you might encounter with your MAXPOWER Adjustable Offset Hex Wrench.
| Problem | Possible Cause | Solution |
|---|---|---|
| Jaws slip on fastener/pipe. | Improper jaw adjustment; Worn jaws; Grease/debris on jaws. | Ensure jaws are tightly adjusted; Clean jaws thoroughly; Replace wrench if jaws are excessively worn. |
| Adjustment nut is stiff or difficult to turn. | Lack of lubrication; Dirt/debris in threads. | Clean threads and apply a light lubricant; Ensure no foreign objects are obstructing the mechanism. |
| Wrench feels loose or wobbly. | Internal wear or damage. | Discontinue use and inspect for damage. If significant, replace the tool. |
7. Specifications
| Specification | Detail |
|---|---|
| Brand | MAXPOWER |
| Model Number | M37401 |
| Size | 12 Inches |
| Material | Ductile Cast Iron Body, Cr-Mo Jaws |
| Jaw Capacity | 1-1/8" (29 mm) to 2-5/8" (67 mm) |
| Finish | Powder Painted (Anti-rust) |
| Item Weight | 1.76 Pounds |
| Head Style | C Shaped, Fixed Square, Hex |
| Operation Mode | Mechanical |
8. Warranty and Support
8.1 Warranty Information
MAXPOWER tools are manufactured to high-quality standards. While specific warranty details may vary, MAXPOWER typically offers a limited warranty against defects in materials and workmanship. Please refer to the product packaging or the official MAXPOWER website for the most current warranty policy.
8.2 Customer Support
For any questions, concerns, or assistance with your MAXPOWER Adjustable Offset Hex Wrench, please contact MAXPOWER customer support through their official website or the retailer where the product was purchased. You can also visit the MAXPOWER Store on Amazon for more information.





