Screwdriver Bit Wera 840/4 Z SB

The Wera 840/4 Z SB screwdriver bit is a precision hex bit designed for reliable fastening tasks. It has a 5 mm hex tip and a hardened shaft with a total length of 152 mm, paired with a 1/4 inch hexagonal shank for compatibility with common bit holders and drivers. Supplied in a blister pack, this bit delivers a secure fit in socket adapters and quick-change chucks and is intended for repeatable, accurate torque transfer in workshop and maintenance environments.

Advantages

The bit combines precise tip geometry with durable material treatment to reduce wear and cam-out. Its 5 mm hex tip provides accurate engagement with fasteners, while the 152 mm length gives added reach for recessed or hard-to-access screws. The 1/4 inch hexagonal shank ensures compatibility with a wide range of manual and powered drivers. The blister packaging protects the bit during transport and storage.

Suitable for

• General assembly and disassembly of small machinery and equipment
• Maintenance and repair tasks in workshops and service vehicles
• Installation of furniture and fittings with 5 mm hex fasteners
• Accessing recessed fasteners where standard short bits cannot reach

Key specifications

• Tip type: 5 mm hexagon
• Total length: 152 mm
• Shank shape and size: 1/4 inch hexagonal shank
• Material and treatment: hardened steel tip and shaft for wear resistance
• Packaging: blister pack for individual protection

How to use

Insert the 1/4 inch hex shank into a compatible bit holder, quick-change chuck, or screwdriver handle. Ensure the bit is fully seated and locked before applying torque. Use steady pressure and align the bit with the fastener axis to minimize slipping. For powered drivers, select an appropriate speed and torque setting to match the fastener and workpiece material. After use, return the bit to its blister pack or store in a suitable holder to prevent damage.

Usage recommendations

Inspect the bit tip before each use for rounding or damage; replace the bit if wear compromises engagement. Use the bit with drivers that accept a 1/4 inch hex shank and match torque settings to the fastener size. Avoid using the bit as a pry tool or subjecting it to lateral loads that can cause breakage.