Most popular e throtle butterfly we sell, wery fast and handle als and huge boost without dump valve. Butterfly flows well to 1300hp. Delivered with bolt on flange to old audi 5 syl 20v s2, s4, s6 rs2 intakes. Price is for a complete kit inklude bolt on flange, or welding flange, contact and butterfly . We can provide pid numbers to this butterfly on demand.