433.92MHz Grey Back Only: Ensure your original remote operates at 433.92MHz and has a grey back. Not compatible with Marantec Digital 868MHz remotes with black back. Not compatible with Marantec Bi-Linked series. Compatibility List: This is a replacement for Marantec 433.92MHz Multi-Bit remote controls. Compatible with Marantec Digital models 302, 304, 306, 313, 317, 318, 321, 323, 382, 384, 392, 394 (433MHz). Compatible with Marantec Command models 131, 132, 222, 231 (433MHz). Compatible with garage door opener receivers operating at 433.92MHz Multi-bit frequency. Suitable for use with Marantec Comfort models 50, 51, 60, 211, 220, 220.2, 250, 250.2, 252, 252.2, 500, 510, 520, 580, 800, 820, 830, 850, 851, 870. Warm Tips: This garage door remote control is a replacement accessory, not an original manufacturer part. Please verify device compatibility using the list above before purchase. Material: Plastic Color: As shown Package Contents: 2 x Remote Controllers Note: Light reflection and differences in display screens may cause slight variations in color representation between the image and the actual item. Measurement may vary by +/- 1-3 cm.