Chain lock FISCHER PROTEC PLUS+ CK100 — robust steel chain with 4-sided links, model 50746

FISCHER PROTEC PLUS+ CK100 is a heavy-duty chain lock designed to secure bicycles and other portable valuables. The lock uses a robust steel chain with four-sided links that increase resistance to sawing and leverage attacks while remaining compact enough for everyday transport. The integrated locking mechanism and solid construction provide reliable protection for routine outdoor use in urban and suburban environments.

Advantages

The four-sided steel links deliver improved shear and bending resistance compared with round-link chains, reducing vulnerability to common cutting tools. The compact chain design balances security and portability, making it practical to carry on a bicycle frame or in a bag. The lock mechanism is engineered for straightforward operation and long-term durability, while the overall build minimises weak points that could be exploited during tampering.

Suitable for

• Securing bicycles in public spaces, racks and bike stands
• Locking scooters, e-bikes and other two-wheelers
• Protecting luggage, tools or equipment during short-term stops
• Use in urban and suburban environments where medium to high resistance is required

Key specifications

• Chain construction: hardened steel with four-sided links for increased cut resistance
• Lock type: integrated cylinder locking mechanism with protective housing
• Use case: outdoor use for bicycles, e-bikes, scooters and portable equipment
• Portability: compact length and flexible links for easy transport
• Finish: corrosion-resistant coating for outdoor durability

How to use

Wrap the chain around the bicycle frame and a fixed, immovable object such as a solid rack or pole, ensuring the frame and, if possible, the rear wheel are enclosed to minimise theft risk. Insert the chain end into the locking cylinder and turn the key or operate the mechanism according to the product’s instructions until locked. When parking, choose well-lit, visible locations and position the chain so that cutting tools have limited access to the links and lock body.

Recommendations

For improved security, pair the chain lock with a secondary lock or use it to secure both frame and wheels. Regularly inspect the chain and lock mechanism for signs of wear, contamination or corrosion and lubricate the cylinder periodically with a suitable lock lubricant to maintain smooth operation.