Abstract: A pad for providing alternating pressure e.g. in a mattress. The pad comprises first and second flexible longitudinal tubes adjacent respective first and second sides of the pad. The pad also includes a plurality of first transverse tubes communicating pneumatically with the first longitudinal tube and each having a closed end remote therefrom and a plurality of second transverse tubes communicating pneumatically with the second longitudinal tube and each having a closed end remote therefrom. The first tubes are disposed at a first angle such that the closed ends of the first transverse tubes are located beneath the second longitudinal tube. The closed ends of the second transverse tubes are disposed at a second angle opposive to the first angle and are located beneath the first longitudinal tube. The first and second tubes are interdigitated so that the arrangement produces a shallow "V".