Unguard bicycle lock Bulldog DT 8012 by ONGUARD — chain lock accessory

ONGUARD Bulldog DT 8012 is a portable chain lock accessory designed to secure bicycles, scooters and similar personal transport. The product combines a hardened steel chain with a keyed locking mechanism to provide practical theft deterrence for everyday urban use. Its compact form factor allows the chain to be carried on the bike or in a bag and used to anchor frames and wheels to fixed objects such as bike racks, posts or railings.

Advantages

The Bulldog DT 8012 features a hardened chain construction that increases resistance to cutting and sawing, and a keyed cylinder for reliable locking and unlocking. Its accessory format makes it easy to integrate with existing mounts and carrying solutions, while the protective sleeve reduces paint damage to frames. The lock is suitable for repeated daily use and balances portability with a focus on practical security.

Suitable for

• Securing bicycles and children’s ride-on vehicles in urban environments
• Locking scooters and small personal transport devices to fixed structures
• Anchoring bicycle frames and wheels during short- to medium-term stops
• Use as an additional security layer together with other locks

Key specifications

• Type: hardened-steel chain lock with keyed cylinder
• Design: portable accessory format for on-bike or in-bag carry
• Protection features: protective sleeve to prevent frame scratching
• Intended use: everyday urban security for bikes, scooters and similar vehicles

How to use

Thread the chain through the bike frame and at least one wheel, then loop it around a fixed object such as a rack or post. Insert the locking end into the keyed cylinder and turn the key to lock; keep the spare key in a separate secure place. Position the protective sleeve between the chain and the painted surfaces to minimise abrasion. For maximum convenience, store the chain in a saddlebag, pannier or dedicated mount when not in use.

Usage recommendations

For improved security, use the Bulldog DT 8012 in combination with a U-lock or additional cable when leaving a bike unattended for extended periods or in high-risk locations. Regularly inspect the chain and lock cylinder for wear or contamination and lubricate the cylinder according to the manufacturer’s guidance to maintain smooth operation.