The device is a mechanical air locking valve that can only be deployed when there is no air in the lines. Upon disconnecting the trailer the driver turns the key, moving a ball valve in place so that no air can be re-introduced into the lines to raise the brakes. The device is plumbed into the air lines and requires a considerable amount of time to circumvent.
Unlike a portable gladhand lock, which can be removed along with the fitting, this device cannot be removed without doing damage to the lines and disabling the trailer's brake system. It is easy to operate, extremely secure and it has a tremendous deterrent value against theft, according to the company. It can be master keyed as well as uniquely keyed to suit the application.
The device can install on most trailer configurations which use air lines either attached to the facing of the trailer or on the undercarriage.
More info: www.rigsecure.com