Screwdriver Bit Wera 851/1 BDC PH

The Wera 851/1 BDC PH screwdriver bit is a single precision bit designed for Phillips screws. It features a diamond-coated tip that improves grip in the screw head, reduces the contact pressure required and lowers the risk of slipping. The bit has a 1/4" hexagon shank compatible with holders to DIN ISO 1173‑D 6.3 and a 25 mm length, providing a compact solution for professional and DIY screwdriving tasks.

Advantages

Diamond particles on the Phillips tip ensure a secure fit in the screw recess and reduce cam‑out. An integrated Torsion zone diverts kinetic energy away from peak loads, while the softer BiTorsion zone prevents the tip from twisting under sudden overloads. These features together extend service life and maintain consistent performance during repetitive use.

Suitable for

• Precision fastening of Phillips (PH) screws
• Use with 1/4" hex holders and quick‑change chucks (DIN ISO 1173‑D 6.3)
• Professional trades and DIY repair or assembly tasks

Key specifications

• Brand: Wera
• Model: 851/1 BDC PH
• Tip type: Phillips (PH)
• Suggested size: PH 3
• Length: 25 mm
• Shank: 1/4" hexagon (DIN ISO 1173‑D 6.3 compatible)
• MPN: 05 056404 001
• EAN: 2050000315602

How to use

Insert the 1/4" hex shank into a compatible bit holder or quick‑change chuck. Place the diamond‑coated Phillips tip into the screw recess and apply steady axial pressure while turning the driver. The Torsion and BiTorsion zones will absorb peak loads; avoid excessive torque beyond the recommended screw or tool limits to prevent damage.

Recommendations

Use the bit for appropriate Phillips screw sizes (PH 3 recommended). Replace the bit if the tip shows visible wear or deformation. For best results, pair with a torque‑controlled screwdriver or driver to avoid overloading and to maximize bit life.