Small:- A versatile low profile back support designed to fit almost any whitewater kayak. Made from wear resistant ripstop fabric‚ a stiff mid section ensures excellent support for increased comfort on longer trips. Large:- A versatile back support designed to fit almost any touring or recreation kayak. Made from wear resistant ripstop fabric‚ a stiff mid section ensures excellent support for increased comfort on longer trips.   Dimensions:- Large 20 cm H x 42 cm W x 3 cm D Small 15 cm H x 35 cm W x 2.5 cm D