The main problem encountered in pulmonary artery banding is the difficulty in determining the optimal perimeter of the band, and sometime repeated surgical operations are required to adjust the band perimeter in order to control the pulmonary blood flow. To overcome these difficulties EndoArt S.A. (Lausanne, Switzerland) developed an externally adjustable, telemetrically controlled device for pulmonary artery banding (FloWatch), which is wireless, battery free, easy to implant and use, and we here report on the technical characteristics of the device. The preliminary acute experimental studies demonstrated the feasibility of the implant and the good functioning of the device.