Wera Bit PH Gr.1 L25mm screwdriver bit, hardened, model 851/1BTZ

Wera Bit PH Gr.1 L25mm model 851/1BTZ is a hardened Phillips (PH) screwdriver bit with a length of 25 mm designed for use in interchangeable screwdrivers and bit holders. The bit's Grade 1 PH geometry ensures accurate engagement with Phillips fasteners while hardening increases wear resistance for prolonged service life in assembly, maintenance and general fastening tasks.

Advantages

The hardened steel construction improves resistance to abrasion and deformation under torque, while the precise PH Gr.1 tip geometry reduces cam‑out and provides secure seating in compatible screw heads. With a standard 25 mm length, the bit offers a balance between accessibility in confined spaces and stability in the tool holder. It is compatible with common 1/4" hex bit holders and quick‑change systems used in workshop and industrial environments.

Suitable for

• Assembly line fastening of Phillips head screws
• Maintenance and repair work on machinery and equipment
• General woodworking and metalworking fastening tasks
• Use with bit holders, ratchets, and interchangeable screwdrivers

Key specifications

• Tip type: Phillips (PH) Grade 1 geometry
• Length: 25 mm
• Material: hardened steel for increased wear resistance
• Shank: 1/4" hex compatible for standard bit holders
• Compatibility: designed for use with interchangeable screwdrivers and quick‑change bit systems

How to use

Insert the 1/4" hex shank of the Wera PH Gr.1 L25mm bit into a compatible bit holder, quick‑change chuck or screwdriver handle until it locks securely. Select the correct PH screw size that matches the Grade 1 tip geometry to ensure proper engagement. Apply steady axial pressure and controlled torque during fastening to minimize wear and avoid cam‑out. For removal, maintain firm seating and reverse the rotation direction while keeping axial pressure to prevent stripping.

Usage recommendations

Use the bit with appropriately rated drivers and torque settings; avoid excessive torque that can damage the tip or fastener. Inspect the bit regularly for signs of wear or deformation and replace when tip geometry is compromised. Store in a dry tool case to prevent corrosion and maintain peak performance.