U-lock bike lock GERDA Ultra 245/165S — hardened shackle security lock

U-lock bike lock GERDA Ultra 245/165S — hardened shackle security lock is a compact, high-strength lock designed to secure bicycles and small vehicles in urban environments. The lock features a U-shaped hardened steel shackle combined with a matching crossbar lock body to provide resistance against cutting, sawing and leverage attacks. It is intended for everyday use to secure frames and wheels to fixed objects during short and medium-duration stops.

Advantages

The GERDA Ultra 245/165S offers a balance of size and security, with a hardened shackle that increases resistance to common physical attacks while remaining compact enough for convenient transport and storage. The crossbar lock body is engineered to work with the shackle for consistent locking performance. Its straightforward design simplifies locking and unlocking, and materials are selected to reduce corrosion and maintain function in urban conditions.

Suitable for

• Securing bicycle frames to bike racks, poles or other fixed objects
• Locking small commuter bicycles and folding bikes during short stops
• Providing additional security for wheels and accessories when used with a secondary cable or chain
• Use in urban commuting, shopping trips and short errands

Key specifications

• Lock type: U-lock (D-lock) with crossbar body
• Shackle material: hardened steel for enhanced cut and leverage resistance
• Design: compact U-shape for frame and wheel anchoring
• Intended use: everyday urban security for bicycles and small vehicles
• Finish: corrosion-resistant treatment suitable for outdoor use

How to use

Place the U-shaped shackle around the bicycle frame and, where possible, through one wheel and around a fixed object such as a bike rack or pole. Align the shackle ends with the crossbar lock body and insert until the mechanism engages. Turn the key or operate the built-in locking mechanism according to the lock’s design to secure the shackle. To unlock, reverse the operation: insert the key or actuate the release and remove the shackle. For transport, attach the lock to the frame-mounted holder or store it in a bag.

Usage recommendations

For improved overall security, use the GERDA Ultra 245/165S together with an additional cable or chain to secure loose wheels or accessories. Choose well-lit, visible locations and avoid leaving the bicycle unattended for extended periods. Regularly lubricate the locking mechanism and inspect the shackle and body for signs of wear or corrosion.