Package Contents: includes 4 door opener remote transmitters compatible with LM123, Remote control frequency is 433.92MHZ, with 4 independent channels; High grade materials and low power technology, durable and fully meet your needs Compatible Models: compatible with for Aleko, for Lockmaster, for Casar and for Topns automatic door openers, compatible with for ALEKO automatic door openers; After more than 100, 000 cycles of equipment testing, it has super strong signal strength and long lasting durability. Strong signal: It can be synchronized with the receiver within one minute, suitable for a variety of different doors, such as garages, gates, workshops, etc.; the 170 foot signal range allows you to open the garage door or gate without getting out of the car, which is more convenient. Easy to Program: to quickly pair with the system through the buttons on the receiver; Enjoy 170 feet of signal range and strong signal penetration to ensure reliable operation in any environment Strong Security: advanced 433.92MHz rolling code technology generates a different signal for each use, preventing the signal from being stolen or copied; Protecting your property from traditional fixed code vulnerabilities and ensuring the security of user access control systems. Colour:As Shown Material:plastic Package Contents: 4 * Remote Control Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +\/- 1-3cm.