... Key Specification-Materials: iron, PP, PVC,foam-easy to assamble-Designed for efficient sit-ups, abdominal work and ... level.3.Four or Six iron springs to support your body.4.When lying down,it will be back ... automatically.5.Use your strength of belly and waist to ... seated postion.9.Total core will help you to get fit with ease and happiness.PACKING DETAILS ...