diff --git a/README.md b/README.md
index cc5d292..0b421e9 100644
--- a/README.md
+++ b/README.md
@@ -33,6 +33,7 @@ See the complete worklog here: (TODO: Link to the Fediverse)
 - Battery holder
 - Power switch
 - A nice case (mine was sold as a tea box)
+- (optional) a couple of resistors to build a voltage divider for the battery level reporting (any value between 1kOhm and 10kOhm will do)
 
 ### Flash the firmware
 
@@ -51,7 +52,7 @@ In any case, the file you have to use is `hexagon.yaml`.
 Find a suitable enclosure, install the switches, speaker, battery holder and ESP8266. Cut the neopixel-compatible led strip in six chunks of two leds, stick it to the 6 sections of the box and solder it according to the electric scheme. Test it all and decorate as you prefer.
 
 You will find useful:
-- the [Electric scheme](doc/hexagon-schematics.pdf) (image, or if you prefer you can open the KiCad project)
+- the [Electric scheme](doc/hexagon-schematics.pdf) (pdf, or if you prefer you can open the KiCad project in `hexagon-schematics` folder)
 - the worklog (TODO: Link to the Fediverse) to see how I built mine
 
 ## Contributing