This cross-over study of twenty five (anticipated) healthy human subjects will utilize two active control devices, and two different widths of the investigational device. One active control is representative of the usual care tourniquet applied in hospital settings. The second active control is a windlass tourniquet representative of the pre-hospital and military usual care tourniquet device. Two inch and four inch widths of the investigational device will be evaluated. The purpose of this study is to characterize and compare investigational and control tourniquet safety and efficacy. All tourniquets will be applied to the upper thigh. Efficacy data is provided by the presence or absence of popliteal flow when assessed with ultrasound. Mapping of interface pressures between the skin and the tourniquet will provide safety data. A minimum washout of five minutes will be allowed between tourniquet applications. All interventions will be applied in one visit. No follow up visit is anticipated.