The most ubiquitous face of insurance is
"Flo from Progressive," whose commercial just happened to come on the TV as I was reading this thread. On a whim, I typed them in, along with "Racing Slicks," and, sure enough, this page came up:
Auto Insurance Coverage Options - Custom Parts and Equipment (CPE)/Accessory Coverage Yes, apparently Flo covers "Racing Slicks," and racing seats, too, but not CB radios. Now, if that's not a compelling reason to take a moment and read your policy, I don't know what is.

But, you gotta love Flo....