Weight Stack: 220 lb x 2 Standard (FF-FSR100-CB-220) *Weight Stack Increments: (20) 11 lb plates per side (Feel like 5.5 lbs per side due to 2:1 ratio) Optional 319 lbs (144 kg) x 2 (638 lbs, 288 kg, combined) (FF-FSR100-CB-319) *Weight Stack Increments: (29) 5 kg (11 lb) plates total (Feel like 5.5 lbs per side due to 2:1 ratio) PLEASE NOTE: Due to variations in the construction of the weight stack holder and other components between the 220 lb and 319lb stacks, upgrading the weight stack at a later time is not possible.