diff --git a/02_Projects/CNC Machining.md b/02_Projects/CNC Machining.md
index 7bff206..93a4509 100644
--- a/02_Projects/CNC Machining.md	
+++ b/02_Projects/CNC Machining.md	
@@ -44,6 +44,9 @@ A CNC router custom-built by a friend, based on the Low Rider design by V1 Engin
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+**Tool Selection Reference**
+- Yvain's tool definition overview: see `attachments/tool-reference-yvain.jpg`
+
 ### Engraving Tools
 
 - **CFH Brandmalkolben Set 30W (BM 245)** - Wood burning tool for engravings
diff --git a/02_Projects/attachments/tool-reference-yvain.jpg b/02_Projects/attachments/tool-reference-yvain.jpg
new file mode 100644
index 0000000..9b6315c
Binary files /dev/null and b/02_Projects/attachments/tool-reference-yvain.jpg differ