The Electro-Craft Reliance Electric BSA Series Brushless Servo Amplifiers consists of high performance square wave current servos that are suited to single or multi-axis applications. We have most if not all models currently in stock. The BSA Series is used to power brushless motors that are equipped with codor feedback as well as the S-Series, F-Series, and LD-Series motors. The BSA series are designed to be mounted on a flat surface in a clean and dry enviornment.