AFCO aluminum, mono-tube design, 79 stroke, big body 2.17" outside diameter, coil-over style (use 20135 kit), non-adjustable valving, user serviceable. 5 valve on compression and 5 valve on rebound with rough track valving. Fine tuning by adjusting gas pressure by Schrader valve, for chassis stability and drive feel. Compressed length 16.21", extended 24.15"