diff --git a/scad/canon_ef_m_bellows_mount.scad b/scad/canon_ef_m_bellows_adapter.scad
similarity index 79%
rename from scad/canon_ef_m_bellows_mount.scad
rename to scad/canon_ef_m_bellows_adapter.scad
index e6fe6d8..accfb57 100644
--- a/scad/canon_ef_m_bellows_mount.scad
+++ b/scad/canon_ef_m_bellows_adapter.scad
@@ -4,7 +4,7 @@ include <./common/common.scad>;
 difference () {
 	union () {
 		ef_m_mount(thickness=2,grip = true);
-		translate([0, 0, -3]) cylinder(r = 38.5 / 2, h = 10, center = true, $fn = 360);
+		translate([0, 0, -3]) cylinder(r = 38 / 2, h = 10, center = true, $fn = 360);
 	}
 	//guide
 	translate([0, 0, -3]) rotate([0, 0, 8.75]) translate([0, -26, 0]) cylinder(r = R(3), h = 4, center= true);