diff --git a/README.md b/README.md
index bc75fd9..1224eb1 100644
--- a/README.md
+++ b/README.md
@@ -6,6 +6,9 @@ Documentation and notes for a Maho MH500W CNC
 
 RAL6011
 
+# Pull Stud (be carefull there is the sort and the long for SK and BT tooling)
+SK40 ISO 7388 II B
+
 ## Selecting Heidenhain EXE
 
 LS-403C has a grating period of 20μm ==> 1 μm resolution in 5 fold interpolation