diff --git a/README.md b/README.md
index 295b921..78587d9 100644
--- a/README.md
+++ b/README.md
@@ -29,6 +29,9 @@ Modules, which are used by users and known to work
 - To build for iGate mode use `pio run -e esp32dev_igate`
 
 # Development board
-Development board schematics, case and antenna models are available under `extras/cad` and `extras/schematics`.
+Development board schematics, case and antenna models are available under `extras/cad` and `extras/schematics`. 
+
+Supported ESP32 boards are with 30 and 38 pinouts (configured with solder pads), 
+NB! **PCB ESP32 socket is for narrow ESP32 boards, such as NodeMCU-32S**.
 
 ![Modes of operation](extras/images/device.png)