diff --git a/follow_focus.py b/follow_focus.py
index 3b2e31c..73cc9aa 100644
--- a/follow_focus.py
+++ b/follow_focus.py
@@ -37,6 +37,7 @@ rod_diameter=        15.2
 offset=              9
 tab_height=          6
 tab_width=           25
+lid_stepper_hole=    5.5
 
 # Gears
 mod=                 0.8
@@ -163,7 +164,7 @@ lid = lid.add(copy)
 
 lid = lid.faces('>Z[1]').workplane().center(stepper_center[0], -stepper_center[1])\
                                     .circle(sg_radius+mod).extrude(lid_thicknesss-wall_width)
-lid = lid.faces('>Z[0]').workplane().circle(5/2).cutThruAll()
+lid = lid.faces('>Z[0]').workplane().circle(lid_stepper_hole/2).cutThruAll()
 
 base = base.faces('<Z[1]').workplane().center(lg_x, lg_y).circle(lg_radius+2*mod).cutBlind(-gear_thinkness-gear_gap)
 base = base.faces('<Z[2]').workplane().circle(support_radius).extrude(-lid_thicknesss+wall_width)