Watchdawg Locking Tractor Parking Brake Air Valve Knob

Protect your truck and your cargo! The Watchdawg replaces the standard yellow tractor parking brake knob. Installs quickly without tools. Flash chrome plated aluminum. Once installed it stays on, making it convenient to on, making it convenient to use anytime -- no more fumbling around with removable locking devices! Perfect for use in tractor-trailer applications as well as RV, buses and more. Made in the USA. 

How it works:

• Remove the yellow knob and install the Watchdawg using one of the included adapters. 
  Pull the knob out to apply the brakes.
• Insert key and unlock, enabling the Watchdawg to slide back and forth.
• Reposition the Watchdawg against the dash and turn the key to lock. Locking the knob against the dash prevents brake release.
• Return the knob to operating mode by using the key to unlock, pull the knob to its outer position and re-lock. The brake valve will now operate normally. 
  
  NOTE: Red trailer knob is not included.