Open-End Box Wrench 28 mm Mastiff KT-30028

The Mastiff Open-End Box Wrench 28 mm KT-30028 is a single-size hand tool designed for tightening and loosening hexagonal nuts and bolts. It combines an open-end jaw and a boxed end in one steel construction to provide versatility for manual mechanical work, repair and assembly tasks. The fixed 28 mm size ensures consistent fit on compatible fasteners, and the boxed end offers secure engagement for higher torque applications.

Advantages

This 28 mm combined wrench offers the practicality of two working ends in a single tool, reducing the need to switch between separate wrenches. The open-end side allows quick placement on nuts in tight or partially obstructed locations, while the boxed end gives a more stable grip for loosening or tightening with greater torque. The one-piece construction provides dimensional stability and reliable contact with fastener faces, helping to minimise rounding of nuts and bolts when used correctly.

Suitable for

• Automotive maintenance and wheel or suspension work where 28 mm fasteners are used
• Industrial machinery maintenance and assembly tasks requiring a fixed-size wrench
• Household and workshop repairs involving 28 mm nuts and bolts

Key specifications

• Tool type: combined open-end and box wrench
• Size: 28 mm fixed jaw
• Material: forged steel construction (hand tool grade)
• Ends: one open-end and one boxed end for secure engagement
• Finish: corrosion-resistant surface treatment suitable for workshop use

How to use

Select the 28 mm Mastiff wrench and position the appropriate end on the fastener. Use the open end to quickly place the tool in confined spaces or when side access is required. For higher torque or to reduce the risk of rounding, place the boxed end fully over the nut or bolt head and turn with steady force. Apply gradual force and ensure the wrench is fully seated on the fastener faces to maintain proper contact and avoid slippage. Store the wrench in a dry tool drawer or on a rack to preserve the finish.

Usage recommendations

Use the boxed end for final tightening or initial loosening when higher torque is needed. Avoid using the open-end for high-torque applications that could damage the fastener. Inspect the wrench for wear or deformation before use and do not apply impact force or use with cheater bars. Keep the tool clean and lightly lubricated to prevent corrosion and ensure long service life.