ARP thread chaser taps for cleaning threads. These cleaners are great for use on engine rebuilds for cleaning the threads in your block and head. Thread chasers clean the threads without "cutting" new threads like a standard tap will do. No need to cut any metal out, just clean the thread holes up with a chaser. M8 and M10 size.
M8= cam tower threads, Intake and exhaust threads, water pump
M10= Head Bolts, main cap bolts