This attendant-operated stair climber works on angled, straight and curved stairs of many types (wood, metal, concrete or carpeted). The LIFTKAR model PT-U (pictured) attaches to a manual wheelchair and is compatible with most standard, transport, sport or pediatric models. Another model (the PT-S) features a built-in seat and does not require a wheelchair. Both models disassemble into three parts that can be easily stored in a car; the heaviest piece is 41 lbs. These stair climbers are battery operated, feature three climbing speeds, and have brake wheels that automatically lock upon reaching the step edge.