Paper Numbers on Cars

OK, so you know those square pieces of paper that people tape in their back windshield? The ones that are red (-ish, since they’re usually faded) with a white number on them (usually 1-10)? Does anyone know what those mean? I see them all the time in cars driving around here (Santa Rosa area, Cali), and I’m curious.

Maybe from the local garage?
Here in Ottawa, dealerships use those so they know which car needs to be worked on etc…
Just my WAG

They are temporary registration stickers. The number signifies the month that the sticker expires.

If you are talking about a small square red piece of paper with a white number on it, then Luden hit it on the head. They are temp registration stickers. Given out by the DMV when fees have been paid, but the more time is needed to complete the registration process.

That’s exactly what they look like, Rick. Thanks to you and luden for answering.

Luden’s answer doesn’t explain why the OP claims it’s numbers ranging from 1-10. What happened to 11 and 12? - Jinx

maybe she just hasnt seen 11 and 12 yet?