The Helix Mobile Stairlift is designed to transport riders downstairs safely and efficiently. The lightweight and portable Mobile Stairlift Helix does not require pre-installed tracks and is able to carry up to 400lbs. This unit was designed for curved staircases, and the powered tracks can move independently of each other, offering a controlled lift up or down any staircase. To prevent injury, it is recommended that the operator be properly trained in the Stairlift's use, and that they first practice descending stairs without a rider. This chair is designed for rounded/circular stairs. Included with the Helix Mobile Stairlift: 1 Battery and Charger, 1 Safety Head Restraint, 2 Keys, 1 Dust Cover, 1 Lap Belt, and 1 Instruction Manual.