During volunteer studies described elsewhere [3] four different cuff designs were used to compress the calf (Fig. 2). Each cuff was inflated to 40 mmHg using a modified inflation system to provide a constant pressure with time. In patient applications each cuff will have its own inflation system and so these tests should not be considered representative of normal clinical practice. However, these studies provide a means of comparing variation in calf compression with cuff geometry alone, independent of inflation protocol.