What Are Those Things on Trailers

They're titled CBBS devices.

California Bureaucratic Bull #### device.

They tend to make rules and tend entire country has to go to the expense of bending to their Will on the outside chance a product or service may cross their state line. ie... all cars have to meet CA EPA guidelines when only 3% of vehicles are registered there.

That's just the tip of the iceberg.

 

Mostly to help with fuel mileage.

I know that the company I drive for figures if they can gain an average of 0.1 mpg of fuel mileage across the fleet of 70 trucks it saves the company $20k annually... Every little bit counts, and can add up very quickly in a fleet of 50 trucks or more.

 

Something you spend more on to add to your trailer then you will save in 5 years, if you do not damage it.