The Duplex Lite Frame is built around the outstanding comfort of the original Duplex Frame and Suspension. The Duplex Lite Frame is a flexible contoured internal frame with rigid, composite stays. The stays transfer weight to your hips via a custom fitted cupped and contoured waistbelt. Contoured shoulder straps are designed to stabilize the load on your back without slipping. All weight is carried on your hip platform, where it belongs – not on your shoulders or lower back.