diff --git a/Sonoff-4CH-and-4CH-Pro.md b/Sonoff-4CH-and-4CH-Pro.md
index 6e2dfaae..89dc18d3 100644
--- a/Sonoff-4CH-and-4CH-Pro.md
+++ b/Sonoff-4CH-and-4CH-Pro.md
@@ -16,7 +16,7 @@ Compared to the 4CH the main differences/improvements of the 4CH Pro are:
 
   - Relays are isolated from mains and can each switch their own circuit (mains or low voltage).
   - With stock firmware special modes are supported (stand-alone schedules, inching, interlocking).
-  - RF receiver (optional key fob required).
+  - RF receiver (optional key fob or Sonoff RF Bridge 433 required).
   - Dual microcontroller, both a ESP8285 and a STM32.
 
 ## Serial Connection