The Huntleigh Flowtron® Excel AC550 SCD is a non-invasive prophylactic system for reducing the incidence of deep vein thrombosis (DVT). The Flowtron® Excel system consists of a pump and a pair of calf or thigh length, single patient use garments. This Huntleigh Flowtron® system may be used on patients at risk of developing deep vein thrombosis and in conjunction with systemic interventions for the high risk patient.