diff --git a/extension_15.scad b/extension_15.scad
new file mode 100644
index 0000000..5d1302e
--- /dev/null
+++ b/extension_15.scad
@@ -0,0 +1,18 @@
+use <spoolmount_a.scad>
+use <spoolmount_b.scad>
+use <torus.scad>
+
+translate([0, 0, 10])
+spoolmount_a();
+
+spoolmount_b();
+
+translate([0, 0, 5])
+difference() {
+    cylinder(h=5, r=42, $fn=500);
+
+    translate([0, 0, -1])
+    cylinder(h=7, r=25, $fn=500);
+    
+    torus(r_major=33.25, r_minor=3.5, ys=1.4, $fn=500);
+}
\ No newline at end of file