Slow Vehicles Must Use Turn-Out

[flowmotion]

Here are some orange examples from Marin County, CA:

Slower Traffic Use Pullouts
Pullout 100 feet
Pullout

There are also many informal gravel pullouts which people will use to be courteous to the aholes (like myself) riding their bumper. California law states you must use the pullout if 5 cars are following. As JN Winkler mentioned, this is on the test.