Check the listing for details. YELLOW transmitter receiver RF Wireless Electric Garage Gate 2 ch Channel b12. Color: Yellow, Condition: New. Listed at 30.32 USD. I made this Instructional video to help explain how this RF unit works. https://youtu.be/kwYo0U3W8vU 2. The way of outputA. Signal keeps 3 seconds-- “1” connect B. Signal self-locking -- “2” connect C. Signal interlock -- “3” connectD. Signal point start--disconnect（check the Circuit diagram for details）3. Learning way and steps1. Press learning key of receiver—the pilot lamp light—release learning key and pilot lamp extinguish , indicate enter into the status of learning. 2. Press any button of the remote control, indicate learning success as the pilot lamp flash 5 times and automatically exit learning state. Receiver automatically exit learning state if you do nothing in 32 seconds.4. Delete memory messagePress the learning key of the receiver—pilot lamp light—hold on pressing over 8 seconds until the pilot lamp extinguish, which indict success to delete the memory message.5. Main Technique DataWorking voltage DC12V/Static working current ≤7mAWorking temperature -40℃ - +80℃Receiving sensitive ≥-105dBmWorking frequency 433MHz Relay capacity 10A 250VAC or 10A 30VDCReceive the type of encoding Learning code, Fixed code, Rolling/Hoping code Maximum storage for transmitter 30pcs of learning or fixed code; 6pcs of rolling code Size 74.5mmⅹ54.5mmⅹ27mm If you would like a FREE catalog of my eBay store, just add a note, or send me a message, during or after check out.