A relaxing chair with a piece of canvas stretched like a hammock.

The backrest side is a hammock-like seat that uses the tension of the canvas to wrap it around. 

On the seat side, the canvas is made into a bag shape, and plywood and urethane foam are put in to provide a stable seating comfort not found in hammocks. The "Sail chair" is a chair that has different comforts for the seat and back, with a single piece of canvas stretched at four points.