The Posture spring is the classic Spring Unit, and has, through the years, proven its worth. It is made from around hourglass shaped springs which are tied together to form a mat. A round helical crosswise connects each single spring to a spring unit.
Different thickness (gauge) of wire in the springs makes a harder or softer mattress. The lower the gauge, the firmer the mattress. The number of springs per mattress type is one of the key quality characteristics of a Posture spring mattress.