Slide over locking wedge style for your tow vehicle. Fits lots of later model GMC and Chevrolet truck and SUV sizes. 88-02 model years, depending. Best thing is to come over and try them. Chevy GM Silverado Suburban Yukon Blazer Tahoe Sierra. We sold the truck we used them on. They worked great. $20 for the pair. Firm price.
*Update. They do not fit an 02 Sierra. I'm attaching a photo of the mirror style they do fit : ) HTH