ButlerBuilt 17" Seat Advantage II Speedway Black 1970092 and the bore size is

and the bore size is prominently engraved in 3/4 in high numbers for easy identification

Direct OEM replacement

1977-1980 Pontiac Grand LeMans

The smooth curves and design of this exhaust system helps remove restriction and keeps exhaust gas flowing smoothly for increased horsepower

ButlerBuilt 17" Seat Advantage II Speedway Black 1970092 and the bore size isSeat and Cover Sportsman Advantage II 17 in Wide 25 Degree Layback HANS Cut Out Black Velour Cover Included Aluminum Natural Racers have chosen BUTLERBuilt Professional Seat Systems for their seating needs for decades. BUTLERBuilt has always been proactive in their approach to seating issues. BUTLER Built works hard to stay abreast of any and all seat related issues since pioneering the first custom built aluminum seat structure for superspeedway