The Joie Roomie Glide bedside crib. This crib features 11 different height levels to fit most mothers' beds safely and accurately. How to use and adjust: Height adjustment: Press the height adjustment button located at the top of the side frame (directly under the Joie logo) and move the frame up or down. Level numbers: Numbers (from 1 to 11) appear inside the small circular indicator hole to accurately show the current height level. Tilt feature (Anti-Reflux): You can adjust one side to be higher than the other by no more than 4 degrees, which helps to slightly raise the baby's head to reduce reflux and gas problems after feeding.