, Relieve the stress on your back with this . This comfortable chair accessory can be used on almost any type of seat including car seats and office chairs. The nylon mesh construction allows air to circulate behind you, keeping your back comfortably cool. The back support attaches to a seat using a strong elastic strap, and can be adjusted up and down for a perfect fit. The ergonomic lumbar support system holds your back at a comfortable position that relieves muscle tension and improves posture.