GENERAL DESCRIPTION Garage door opener remote control for 4020 TX03-868-4. 868 MHz frequency 4-channel garage door remote control, designed for use with several specific models. Replacement garage door opener remote control, not original. TECHNICAL SPECIFICATIONS Garage door remote control Modern and compact stainless steel design Casing with stainless steel insert to prevent accidental activation Practical clip on the back for optional keychain mounting Rolling code to prevent reading and interception of radio signals Range: approx. 50 m (depending on surroundings) Sliding cover to prevent accidental opening Battery: 3V, CR2 (integrated) Dimensions: 87 x 24 x 16 mm (closed) Compatible devices: 4020 TX03-868-4, 4026 TX03-868-2, 4020V000, 4026V000, 4021, 4025/4025V000, 4031/4031V000, 4035/4035V002 High-frequency contact INSTALLATION STEP 1: Radio receiver on the circuit board (red button, or marked CODE or RADIO). STEP 2: Press the learning button (A) on the radio receiver. STEP 3: Press the desired button on the handheld transmitter (B). The handheld transmitter sends the radio code to the receiver. STEP 4: Repeat the above procedure to program other transmitters.