5.5mm Hex Nipple Driver

The 629TBI-US is Unior's 5.5 mm socket wrench with the three-component TBI handle. It is a 6-point socket that fits over a 5.5 mm hex. Unior's bike catalogue lists this size under wheel tools. Use it on spoke nipples whose heads are a 5.5 mm hex. A slot-head or square-head nipple needs a different driver.

The published working length C is 125 mm. The blade is premium hard chrome vanadium steel, hardened and tempered, then chrome plated. The handle is the three-component TBI shape with a hanging hole. The tool is made to DIN 3125.

This listing is not the 1751/2Q square nipple driver and not the 1751/2 slotted driver. Those take a square head or a slot. The 629TBI-US takes a 5.5 mm hex.

Compatibility

• 5.5 mm hex heads, including external-hex spoke nipples
• Not a hex key for an internal hex recess
• Not the 1751/2Q inverted square nipple driver
• Not the 1751/2 slotted nipple driver

Specs

• Article 629TBI-US, code 625213
• Socket 5.5 mm, 6-point
• Working length (C) 125 mm
• Shaft diameter (D) 6 mm
• Overall length (L) 235 mm
• Weight 103 g
• Blade: premium hard chrome vanadium steel, hardened and tempered, chrome plated
• Handle: three-component TBI, hanging hole
• Standard: DIN 3125
• Official page carries Unior's lifetime-warranty and trivalent-chrome profile badges

All listed dimensions are in millimetres and may vary in tolerance. Weight is in grams.

Built in Zreče, Slovenia

Unior has been forging hand tools in Zreče since 1919, and sponsors professional road and mountain-bike race teams. The 629TBI-US is the 5.5 mm TBI socket in that family. Published working length is 125 mm; the socket is 6-point.

Pro tip from our mechanics

Seat the socket fully on the hex before you add torque. A cocked socket rounds the head, and the next turn is worse. After the nipples are started, true and dish the wheel on a stand. The procedure is in How to true a bike wheel →.

FAQ

What does the 629TBI-US fit? It is a 5.5 mm 6-point socket wrench. The socket fits over a 5.5 mm hex head, including external-hex spoke nipples. Unior's bike catalogue lists this size under wheel tools. It is not a hex key for an internal recess.

Is this a driver for internal hex-recess nipples? No. Official Unior copy calls this a socket wrench with a TBI handle. The published profile is a 6-point socket, and the photo is a hollow socket, not a hex key. A nipple with an internal hex recess needs a hex key, not this tool.

What are the official dimensions and weight? Code 625213, article 629TBI-US. Socket 5.5 mm, working length C 125 mm, shaft D 6 mm, overall L 235 mm, 103 g. Dimensions are in millimetres and may vary in tolerance. The official spare-parts list is empty.

Is this the same as the 1751/2Q square nipple driver? No. 1751/2Q drives 3.2 mm square-head nipples. 1751/2 is the slotted nipple driver. The 629TBI-US takes a 5.5 mm hex. Three articles, three jobs.