BackJoy SitSmart Posture Core UpRight Ergonomic Seating Correction OnyxDescriptionSpecificationsShipping BackJoy is an effective seating solution specially designed to help relieve and prevent back complaints. BackJoy creates an active sitting position and corrects the sitting position, making sitting upright easy. The Posture Core has been specially developed for adults with a weight between 50 125kg, with double the cushioning and a wider seating surface for maximum comfort when sitting for longer periods of time.