Everyway4all EverTrac Taiwan LT100 Lumbar back support adjustable personal belt Demo : https://www.youtube.com/watch?v=Ja4OQikbDDQ&feature=youtu.be your lower back or lumbar region is pulled forward by your knee adjustable the belt length from your knees to your lower back Assistive Posture Support will help you to sit upright with both your knees closed to each other while slightly bent The newest patent , Assistive Posture Support (APS)