Tech & Installation

Turn key and the lock cylinder will pop out allowing the black pin to drop down. Then slide the orange lock frame over your stamped steel coupler flange.

Lift the black pin up until it fits flush with the bottom of the orange lock frame.

With key in the straight up and down, push the key and lock cylinder into the lock and rotate 90 degrees to lock the black pin in place. Your trailer is now secure!

Not all couplers are the same

What is a stamped steel coupler?

Stamped steel coupler

Stamped steel couplers are formed from a single piece of steel which creates a flat lip flange around the base of the coupler.

Madlock utilizes this flanged lip for it’s secure fit & function. Stamped steel couplers are the most common type on the market.

If you are in doubt, please enquire.

Cast coupler

Some couplers more common in industrial applications are manufactured with “cast steel” and do not feature a prominent flat lip flange at the base.

If you have a cast coupler Madlock will not currently fit your trailer. Our next design is in progress.  

Do you have multiple trailers?

Madlock trailer locks can also be ordered as keyed alike as a pair or multiples.