For most players, they just want to keep the hoop at the regulation height of ten feet all the time. But if you have kids (or like to re-enact Dr. J slams), you might be interested in a good height adjustment system to make it easier to reach the rim. Height adjustment system comes it a bunch of different shapes and sizes, but they are usually involve either a hand crank, a pneumatic (gas-powered) system or a pin-lock system. If you are deciding between a pneumatic system and a hand crank, get the hand crack. Pneumatic, because it is more advanced sounds like a better deal, but in my experience hand crack systems are always easier to adjust.