Adjustable footrest increases comfort by placing you in an ergonomically correct position to avoid back, neck & leg strain & fatigue, which can lead to pain & discomfort. Use your feet to control the tilt angle adjustment (from 20 degrees to negative 20 degrees) on the platform. Manually adjust the height adjustment to 4" or 4-3/4". Adjustable footrest also features a nonskid foot platform with soft bumps to massage & soothe your feet. Durable, heavy-duty steel base stays in place.