On the Golden Gate Bridge in San Francisco, traffic patterns vary a lot throughout the day. So when traffic authorities decided to install a heavyweight concrete barrier dividing the northbound lanes from the southbound ones, they decided they wanted it to be moveable.

We’re not here to talk about traffic patterns, though. We’re here to talk about what may be our favourite traffic-management vehicle of all time (and the competition is stiff): the “Road Zipper”. The cheerful yellow truck drives down the row of 3,500 concrete blocks, each of which weighs 1,500 pounds, and shifts them one lane over. It’s basically like a giant concrete zip:

The barrier was installed earlier this month, and the bridge was reopened to normal traffic on 11 January. The system cost around $30m to install.

Here’s a video of the truck in action:

“Barrier Transfer Machines”, as they’re more generally known, are used to manage traffic in several cities in the US and Australia, and cities around the world use them during construction work. We haven’t been able to find one in quite such a cheerful shade of yellow, though. 

h/t: Laughing Squid.