Review on Gorilla Automotive SP601 S Spacer Applications by James Dominick

As the name suggests. They work well, fit all types of bolts, but don't expect any vibration. I've been trying for days to get rid of the vibration with these spacers on my Subaru STI and finally just gave up. Instead I bought some CNC machined hubs and the VIBRATIONS WERE GONE! If you put them on a truck or car with huge 65mm sponge sidewalls they'll be fine, but if you have 40mm autocross tires you'll feel EVERY vibe from these.