Screwdriver bit set Wera 851/4 Z Phillips PH1, 4.5 mm shank, 70 mm length

The Wera 851/4 Z Phillips PH1 screwdriver bit is designed specifically for driving PH1 cross-head screws. With a 4.5 mm shank diameter and a 70 mm overall length, this bit fits standard bit holders and power screwdrivers that accept common 1/4" hex or cylindrical bit interfaces. The tip geometry is made to match PH1 fasteners precisely, reducing cam-out and improving torque transfer for controlled fastening in assembly, electronics and general repair tasks.

Advantages

This Wera PH1 bit offers a precise fit to PH1 screws and consistent torque transmission. The 70 mm length provides extended reach in recessed or hard-to-access areas while the 4.5 mm shank ensures compatibility with a wide range of bit holders and impact drivers. The bit is manufactured to maintain tip shape under repeated use, supporting repeatable performance in assembly and maintenance work.

Suitable for

• Electronics assembly and small appliance repair
• Furniture and cabinet assembly where PH1 screws are specified
• Household maintenance and do-it-yourself projects
• Light mechanical and electrical installations

Key specifications

• Tip type: Phillips PH1
• Shank diameter: 4.5 mm
• Overall length: 70 mm
• Material and hardness: manufactured to Wera quality standards for wear resistance (tip retention and torque stability)
• Compatibility: designed for standard bit holders and power screwdrivers that accept 4.5 mm/1/4" style bits

How to use

Insert the 4.5 mm shank of the bit into a compatible bit holder, chuck or quick-change adapter until it seats securely. Position the PH1 tip into the screw head, apply steady axial pressure and engage the driver at an appropriate speed or torque setting to avoid stripping. For power tools, start at low speed and increase as required, monitoring engagement to maintain alignment and prevent cam-out.

Recommendations

Use the bit with an appropriate torque-limiting driver or adjustable clutch when working on sensitive assemblies. Inspect the tip before use and replace if signs of rounding or wear are visible to maintain secure engagement and prevent damage to screw heads.