Bowflex Revolution 80 lb. SpiraFlex Upgrade Boosts resistance from 220 lb. to 300 lb (upper body) or 600 lb. (lower body) Boosts resistance from 220 lb. to 300 lb (upper body) or 600 lb. (lower body) Cutting-edge, non-metal-plate technology looks just like free weight plates Works independent of gravity to provide resistance without adding bulk or weight Easy to install