Includes 4 each 22.5 lb plates and 4 each long locking screws. You can put the "big" plates on the handles first (recommended) or add them on top of the original plates. Very simple to use. The longer locking screws allow dumbbell sizes of 70-120lbs. The standard Quick-Lock dumbbell rack will hold the full 120 lb dumbells. The dumbbells are 19" long overall at the full 120 lbs.