diff --git a/README.md b/README.md
index 7258b51..4e5fdbf 100644
--- a/README.md
+++ b/README.md
@@ -13,5 +13,13 @@
     * DC power jack
 * Potentionmeters to adjust sound level and led brightness level
 * Resistors
+* Switch
+    * general power switch
+    * light switch
+* [LED filament](https://en.wikipedia.org/wiki/LED_filament)
 
-## Software
\ No newline at end of file
+## Software
+
+## Reference
+
+## STL / 3d printing
\ No newline at end of file