NxStage Medical, Inc. (NxStage)is a medical device company that develops, manufactures and markets products for the treatment of kidney failure, fluid overload and related blood treatments and procedures. The Company’s primary product is the NxStage System One (System One). It also sells needles and blood tubing sets primarily to dialysis clinics for the treatment of end-stage renal disease (ESRD). The Company operates in two segments: System One and In-Center. It distributes its products in three markets: home, critical care and in-center. In the System One segment it sells and rents the System One, PureFlow SL equipment and disposable products in the home and critical care markets. In the In-Center segment, it sells of blood tubing sets and needles for hemodialysis at dialysis centers and needles for apheresis. The Company’s products include the NxStage System One, Streamline Blood Tubing Sets and AV Fistula and Apheresis Needles.