Screwdriver Bit Wera 840/4 Z SB

The Wera 840/4 Z SB screwdriver bit is a precision hex bit engineered for accurate fastening tasks. Featuring a 3 mm hex tip and an overall length of 152 mm, this bit combines reach and control for work in recessed or hard-to-access locations. Its 1/4 inch (25.4 mm) hexagonal shank ensures secure seating in bit holders, ratchets and power tool adapters. Supplied in a blister pack, the bit is designed to integrate into professional and hobby toolkits where consistent fit and durability are required.

Advantages

The bit delivers a precise fit to hex fasteners, reducing cam-out and wear. Its extended 152 mm length improves access to deep-set screws while maintaining torque transfer through the hexagonal shank. The design emphasizes material strength and dimensional accuracy for repeatable performance and longer service life. The blister packaging protects the bit during storage and transport and allows easy identification.

Подходит для

• Работы с сантехническими и мебельными соединениями, где требуются 3 мм шестигранные крепления
• Сборки и разборки электроники и приборов с глубокими или труднодоступными винтами
• Использования с держателями бит, трещотками и адаптерами для шуруповертов

Key specifications

• Tip type: 3 mm hexagon
• Overall length: 152 mm
• Shank shape and size: 1/4 inch (hexagonal)
• Packaging: blister
• Material characteristics: engineered for dimensional accuracy and wear resistance

How to use

Insert the 1/4 inch hexagonal shank into a compatible bit holder, ratchet or power tool adapter until it seats securely. Engage the 3 mm hex tip with the corresponding fastener head and apply steady torque appropriate to the screw and material. For manual operations, ensure correct alignment to avoid stripping; for powered tools, use controlled speed and torque settings. After use, store the bit in its blister or a designated holder to protect the tip and maintain accuracy.

Usage recommendations

Use the bit with matching 3 mm hex fasteners and tools that accept a 1/4 inch shank. Avoid excessive lateral force or impact that can deform the tip. Inspect the bit regularly for wear and replace when tip geometry is damaged to preserve fastening quality and safety.