Box End

A box end is a type of wrench head characterized by a closed loop that fully encloses the nut or bolt head. This design contrasts with open-end wrenches, which have a U-shaped opening. Box end wrenches are typically manufactured with either a 6-point or 12-point configuration inside the loop, referring to the number of internal contact points the wrench makes with the fastener.

Advantages of Box End Wrenches:

• Reduced Slippage: The enclosed design provides more contact area with the fastener compared to open-end wrenches, reducing the likelihood of slippage and rounding off the corners of the nut or bolt.
• Higher Torque Application: The full enclosure allows for the application of greater torque without damaging the fastener.
• Accessibility in Tight Spaces: While not always the case, some box end wrenches, particularly those with an offset design, can be more suitable for accessing fasteners in confined spaces.

Types of Box End Wrenches:

• Standard Box End: The most common type, with the wrench head positioned in line with the handle.
• Offset Box End: The wrench head is angled relative to the handle, providing clearance over obstructions and improved access.
• Flare Nut Wrench (Line Wrench): A specialized box end wrench with a small opening or "split" in the side to allow it to slip over hydraulic lines or tubing. While technically a box end derivative, the split weakens the structure, so it's primarily used for flare nuts which require less torque.
• Ratcheting Box End: Incorporates a ratcheting mechanism that allows the wrench to be repositioned on the fastener without removing it, speeding up the tightening or loosening process.

Materials and Construction:

Box end wrenches are typically made from hardened steel alloys, such as chrome vanadium steel, for strength and durability. They are often chrome-plated for corrosion resistance.