Screwdriver Bit Set DeWALT DT7399T-QZ 5 pcs Torx T40 50 mm

The DeWALT DT7399T-QZ 5 pcs Torx T40 50 mm screwdriver bit set contains five identical Torx T40 bits with a 50 mm working length. Produced for use with power drivers and hand-held screwdrivers that accept standard 1/4" hex shanks, these bits provide consistent fit with T40 fasteners. The set is supplied in a compact storage box that protects tips from damage and keeps bits organised for transport and on-site use.

Advantages

Bits are manufactured to provide reliable engagement with Torx T40 heads, reducing cam‑out and wear during repeated fastening operations. The 50 mm length offers improved access to recessed or hard-to-reach fasteners while maintaining control. The compact case enables neat storage and quick selection of a replacement bit when needed. Materials and heat treatment used in production ensure good tip durability for general workshop and trade use.

Suitable for

• Automotive and mechanical assembly where T40 fasteners are used
• Furniture assembly and repair involving Torx screws
• Construction, maintenance and installation tasks requiring extended reach
• Workshops and professional trade kits as a spare or replacement set

Key specifications

• Bit type: Torx T40
• Quantity: 5 pieces
• Working length: 50 mm per bit
• Shank interface: 1/4" hex compatible
• Storage: compact protective box

How to use

Select a Torx T40 bit from the box and insert the 1/4" hex shank into the chuck or bit holder of your power driver or manual screwdriver. Ensure the bit is seated securely before applying torque. Use steady pressure and align the bit with the screw head to minimise slipping. For recessed screws, the 50 mm length gives additional reach; take care to maintain control at higher torque settings to avoid stripping the fastener.

Usage recommendations

Inspect bits regularly for tip wear and replace worn bits to prevent damage to screw heads. Match torque settings on power tools to the fastener and material to reduce risk of over‑tightening. Store bits in the supplied box to protect tips and keep the set together for easy access on the job.