Receiver is built in automatic window opener, no need extra receiver (transformer) ^^Travelling distance of electric window opener can be manual adjusted by stroke adjustable knob from 3.93 inch to 15.74 inch, convenient and quick^^Wide voltage AC100-240V input is suitable for national voltage standards. ^^Obstructing stop function, ensuring the safety of motor operation and protecting system structure is not destroyed^^Super mute design, low noise