Screwdriver Bit Set Wiha 42109

The Wiha 42109 screwdriver bit set contains five Torx T15 bits, each 29 mm long with a 1/4" (25.4 / 4 mm) shank and a total weight of 54 g. The set is designed to simplify bit selection by focusing on the screw shape: these TY (Torx/Y) bits fit both T-shaped and Y-shaped screws and are suitable for a wide range of fastening tasks and materials. A patented torsion zone allows safe use with power tools and impact drivers and extends service life compared with standard bits. The fluorescent, coloured finish improves visibility and makes bits easier to locate, even under UV light.

Advantages

The TY design covers both Torx and Y-type screws so a single bit type replaces multiple variants, reducing the need to carry many different bits. The patented torsion zone absorbs torque peaks when using power tools or impact screwdrivers, providing longer life and consistent performance. Fluorescent coating and colour coding speed up identification and reduce loss of bits.

Suitable for

• Precision fastening tasks requiring Torx T15 size
• Use with manual screwdrivers and 1/4" bit holders
• Power tools and impact drivers (thanks to torsion zone)
• Maintenance, electronics assembly and general workshop work

Key specifications

• Model: Wiha 42109
• Bit type: TY (Torx/Y), size T15
• Quantity: 5 bits
• Bit length: 29 mm
• Shank: 1/4" (25.4 / 4 mm)
• Weight: 54 g (set)
• EAN: 4010995421090

How to use

Select the T15 TY bit and insert it into a compatible 1/4" bit holder, manual screwdriver or power tool. Ensure the bit seats fully in the screw head before applying torque. When using an impact driver or high-torque tool, allow the torsion zone to absorb torque peaks by applying steady pressure and avoiding sudden, excessive force.

Usage recommendations

For best results, match the T15 TY bit to the screw head size, keep bits clean and free of debris, and store them in their case to maintain the fluorescent finish and avoid loss. Replace excessively worn bits to prevent damage to screw heads.