Torx Screwdriver

The straight-shaft Torx in a single size, with a security-Torx-compatible tip. Buy the one you reach for most, in the format that handles deep-recess Torx fasteners a T-handle or Y-handle can't enter. Available individually across the Torx sizes the 621 line covers.

The straight-shaft Torx is the format for two specific situations on a bike: deep-recess Torx fasteners (some derailleur hangers, some shifter-clamp covers), and the security-Torx variants that show up on certain e-bike battery hardware and some component fasteners where the manufacturer wants to make casual tampering harder. The tip geometry on this screwdriver engages both standard Torx recesses and the security-Torx with a center hole (sometimes called Torx-tamper-resistant or "security Torx").

The chrome-vanadium shank is hardened and tempered. The tip is black-oxide treated for corrosion resistance and a precise fit into the Torx recess. The black-oxide finish is the deliberate alternative to chrome plating for the tip: chrome plating adds a small amount of dimensional thickness, which on a Torx tip is the difference between a clean engagement and a tip that bottoms out before fully seating. The non-tip shank surfaces still carry trivalent chrome to ISO 1456:2009 for the corrosion resistance the rest of the tool needs.

Compatibility

The 621 line covers the Torx sizes used most often on bikes, sized per individual order. The most-reached sizes:

• T25: 6-bolt disc rotor bolts (the industry-standard rotor interface; covered by the security-Torx tip)
• T27: Some SRAM disc-brake hardware
• T30: Current Shimano and SRAM chainring bolts; some crank-arm fixing bolts

The straight-shaft format earns its place anywhere a Torx fastener sits below a recess that fouls a T-handle or Y-handle's cross-bar geometry.

Specs

• Single-size straight-shaft Torx screwdriver (size selected at order)
• Hardened, tempered steel blade
• Black-oxide tip treatment for corrosion resistance and recess fit
• Tip compatible with both standard and security-Torx (center-hole) recesses
• Three-material composition handle
• Hex bolster at the handle base for wrench-assist torque
• Trivalent chrome plating to ISO 1456:2009 on the non-tip shank surfaces
• Manufactured in Slovenia

Built in Zreče, Slovenia

Unior has been forging hand tools in Zreče since 1919, and is the official technical partner of multiple World Tour and downhill teams. The straight-shaft Torx screwdriver is the deep-recess counterpart to the T-handle and Y-handle Torx tools in the line; the security-Torx tip geometry is the same tip you'd find on the pro-shop Torx set, which means it covers both standard and security-Torx recesses without two separate tools in the drawer.

Pro tip from our mechanics

E-bike battery and motor-cover fasteners are where security-Torx most often shows up on a bike, alongside some component manufacturers' choice to use it on warranty-seal bolts. If a Torx bolt has a small raised pin in the centre of the recess, that's a security-Torx; a standard Torx driver won't engage. The 621 line's tip geometry handles both, so the same tool that drives a rotor bolt drives the battery-cover screw.

For the Torx-to-fastener map on a typical bike and the access-condition decisions between straight-shaft, T-handle, and Y-handle formats: Hex and Torx wrenches: how to pick the right tool for the job →.