diff --git a/README.md b/README.md
index 8861895..ade2dec 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,7 @@ Information about the LOCO Track Primary HGD4 GPS tracker
 | Unspecified Pressure Sensor    | Pressure Sensor           | -                                            | IC5          |
 | Red LED                        | LED                       | -                                            | LED1         |
 | Green LED                      | LED                       | -                                            | LED2         |
+| Button                         | Push Button               | Wakes the device power off                   | SW1          |
 
 What we know about the pins of the nRF52840 so far: