High Speed CNC spindle Motor WS55-140 ER11 300W Bracket Motor Driver Controller. ER11 collet -(3.175mm). Thank you for your support. We are not responsible for undeliverable address. Dear friend, your happy is very important to me! . We stand behind every product we sell. You can enjoy top-quality product and high-quality services from us, Trust me that you will have a pleasant shopping experience in here. We will be happy to assist you. We would try our best to serve you with any question / problem.