diff --git a/cad/parts.txt b/cad/parts.txt
new file mode 100644
index 0000000..4f5c238
--- /dev/null
+++ b/cad/parts.txt
@@ -0,0 +1,2 @@
+149 mm by 124 mm metal sheet, 99.5% aluminum, 0.2mm thickness
+or: AlMg3, 0.3mm thickness