As most locks have different lengths, we have created a new metric called the Lock Mass Index (LMI), which takes into account both the weight and length of a lock, enabling you to compare bike locks. The LMI is simply the weight of the lock in kilograms divided by the length (or circumference) in metres. The lower the LMI number the better.

Here are the LMI numbers for a selection of best-selling Sold Secure Silver bike locks, demonstrating which is the best bike lock in terms of LMI. As you can see our Litelok Silver range has the best LMI. Overall they are 40-50% lighter than the average equivalent U/D locks, chains and armoured cables.

Who is Sold Secure?

Sold Secure is the premier independent testing and certification house for security products in the UK. Established in 1992 by the Northumbria and Essex Police with the help and backing of the Home Office. Sold Secure is now owned and administered by the Master Locksmiths Association (a not for profit trade association). They have close ties with many police forces and insurers in the UK, who provide Sold Secure with regular information on modern theft methods and the tools used by criminals.

Sold Secure Ratings Explained

Sold Secure have a three tier security grading system, of which Sold Secure Gold is the best, followed by Sold Secure Silver and then Sold Secure Bronze. Gold rated locks offer the highest level of security. Silver rated locks offer a compromise between cost and security. Bronze rated locks typically offers defence against the opportunistic thief.


You can see Litelok Silver listed on the Sold Secure website here.