diff --git a/cad/adapter/adapter.scad b/cad/adapter/adapter.scad
new file mode 100644
index 0000000..835a081
--- /dev/null
+++ b/cad/adapter/adapter.scad
@@ -0,0 +1,37 @@
+$fn = 100;
+
+// element dimensions
+w = 59;
+d = 28;
+h = 4;
+
+// aditionnal parameters
+e = 3;
+
+translate([0,0,e/2]);
+cube([w,d,e/2], true);
+module tab() {
+    translate([-e/4,0,(e/2+h)/2]) {
+        cube([e/2,2*e,h], true);
+        translate([-1.75*e,-e,h/2])
+        rotate([0,-90,-90])
+        linear_extrude(height = 2*e)
+        polygon([[0,e],[e/4,e],[0,2*e],[e/2,2*e]],
+                [[0,1,3,2]]);
+    }
+}
+
+translate([w/2,-0.35*d,0])
+tab();
+
+translate([-w/2,0,0])
+rotate([0,0,180])
+tab();
+
+translate([8,d/2,0])
+rotate([0,0,90])
+tab();
+
+translate([0,-d/2,0])
+rotate([0,0,-90])
+tab();
diff --git a/cad/encoder.scad b/cad/encoder/encoder.scad
similarity index 100%
rename from cad/encoder.scad
rename to cad/encoder/encoder.scad