Trelock Bicycle U-Lock U4 Flex ZB 401 (102x230 mm) + Loop Cable, Black

Your bike deserves more than a “hope it’s still there” kind of lock. The Trelock U4 Flex is built for riders who want reliable security without carrying oversized, heavy hardware.

The 14 mm hardened steel shackle creates a solid barrier against theft attempts, while the drill-resistant cylinder adds an extra layer of protection. Rated 13/18 on the Trelock security scale, this U-lock is ideal for daily city use — commuting, running errands, or locking up outside your favorite café.

What makes the U4 Flex even more practical is the included Loop cable. It allows you to secure your front wheel or attach an additional component at the same time. The sliding keyhole cover protects the locking mechanism from dirt and moisture, while the rubber coating prevents scratches on your frame.

With the included ZB 401 mounting bracket, the lock travels securely on your bike frame — no backpack required.

Technical specification

• Product type: Bicycle U-lock

• Model: U4 Flex 102-230 ZB 401

• Brand: Trelock

• Inner dimensions: 102 x 230 mm

• Shackle diameter: 14 mm

• Material: Hardened steel

• Security level: 13/18 (Trelock scale)

• Cylinder: Drill-resistant

• Keyhole protection: Sliding dust cover

• Coating: Rubberized surface to protect bike paint

• Additional security: Loop cable included

• Mounting system: ZB 401 bracket included

• Keys: Included

• Key replacement option: Available via Trelock website

• Color: Black

• Weight: 1400 g

Intended use:
Daily urban bike security. Suitable for city bikes, trekking bikes, MTB and gravel bikes.

Shipping:
We ship within Poland, across the entire European Union, and worldwide