The 420K/150HB140 USH U-Lock features a 14mm round shackle and a hardened lock body for enhanced security. Its double-bolt locking mechanism offers superior resistance to tampering, while the USH bracket fits securely on 24-35mm tubes. Certified with Sold Secure Gold approval, this lock’s improved design minimizes rattling, ensuring a quieter and more reliable ride. Ideal for serious cyclists seeking robust protection.