diff --git a/holder/holder.scad b/holder/holder.scad
index 95e0eea..a6ace51 100644
--- a/holder/holder.scad
+++ b/holder/holder.scad
@@ -3,53 +3,73 @@ include <../tray/common.scad>
 u2 = 89;
 rw = 482.6;
 
-holder_size   = [tray_size[0]+5, u2, tray_size[2]+3*2+36];
+holder_size   = [tray_size[0]+5, u2, tray_size[2]+3*2+20];
 holder_margin = 7.5;
 
 top_size = 5;
 bottom_size = 11;
 
+holder_pillar_spacing = 3;
+holder_pillar_size = (holder_size[1]-tray_size[1])/2-holder_pillar_spacing;
+
+stud_size = [5, 2.5];
+
 module holder() {
     color("#a0a0a0") difference() {
         translate([-5.01, 0, -3]) union() {
             // base
-                            translate([0, 2.5-(holder_size[1]-tray_size[1])/2,                0]) cube([holder_size[0], (holder_size[1]-tray_size[1])/2, bottom_size]);
-            mirror([0,1,0]) translate([0, 2.5-(holder_size[1]-tray_size[1])/2 - tray_size[1], 0]) cube([holder_size[0], (holder_size[1]-tray_size[1])/2, bottom_size]);
-                                                                                                  cube([5,              tray_size[1],                    bottom_size]);
-                            translate([holder_size[0]-holder_margin, 0, 0])                       cube([holder_margin,  tray_size[1],                              3]);
-
-            // top
-            translate([0, 0, holder_size[2]-top_size]) {
-                                translate([0, 2.5-(holder_size[1]-tray_size[1])/2,                0]) cube([holder_size[0], (holder_size[1]-tray_size[1])/2, top_size]);
-                mirror([0,1,0]) translate([0, 2.5-(holder_size[1]-tray_size[1])/2 - tray_size[1], 0]) cube([holder_size[0], (holder_size[1]-tray_size[1])/2, top_size]);
-                                                                                                      cube([5,              tray_size[1],                    top_size]);
-                                translate([holder_size[0]-holder_margin, 0, 0])                       cube([holder_margin,  tray_size[1],                    top_size]);
-            }
+                            translate([0, -(holder_size[1]-tray_size[1])/2,                0]) cube([holder_size[0], (holder_size[1]-tray_size[1])/2+2.5, bottom_size]);
+            mirror([0,1,0]) translate([0, -(holder_size[1]-tray_size[1])/2 - tray_size[1], 0]) cube([holder_size[0], (holder_size[1]-tray_size[1])/2+2.5, bottom_size]);
+                                                                                               cube([5,              tray_size[1],                        bottom_size]);
+                            translate([holder_size[0]-holder_margin, 0, 0])                    cube([holder_margin,  tray_size[1],                                  3]);
 
             // pillars
-            translate([0, 2.5-(holder_size[1]-tray_size[1])/2, 0]) {
-                                                                                                   cube([5, (holder_size[1]-tray_size[1])/2-3, holder_size[2]]);
-                translate([0, holder_size[1]-2-(holder_size[1]-tray_size[1])/2, 0])                cube([5, (holder_size[1]-tray_size[1])/2-3, holder_size[2]]);
-                translate([holder_size[0]-5, holder_size[1]-2-(holder_size[1]-tray_size[1])/2, 0]) cube([5, (holder_size[1]-tray_size[1])/2-3, holder_size[2]]);
-                translate([holder_size[0]-5, 0, 0])                                                cube([5, (holder_size[1]-tray_size[1])/2-3, holder_size[2]]);
+            translate([0, -(holder_size[1]-tray_size[1])/2, 0]) {
+                
+                     cube([holder_pillar_size, holder_pillar_size, holder_size[2]]);
+                
+                translate([0, holder_size[1]-2-(holder_size[1]-tray_size[1])/2+5, 0])
+                     cube([holder_pillar_size, holder_pillar_size, holder_size[2]]);
+                
+                translate([holder_size[0]-(holder_pillar_size), holder_size[1]-2-(holder_size[1]-tray_size[1])/2+5, 0])
+                     cube([holder_pillar_size, holder_pillar_size, holder_size[2]]);
+                
+                translate([holder_size[0]-(holder_pillar_size), 0, 0])
+                     cube([holder_pillar_size, holder_pillar_size, holder_size[2]]);
             }
 
             // studs
-            translate([(holder_size[1]-tray_size[1])/4, -(holder_size[1]-tray_size[1])/4, holder_size[2]+2.5]) {
-                                                                                                                               cylinder(h=5, r=2.5, center=true);
-                translate([holder_size[0]-(holder_size[1]-tray_size[1])/2, 0, 0])                                              cylinder(h=5, r=2.5, center=true);
-                translate([0, holder_size[1]-(holder_size[1]-tray_size[1])/2, 0])                                              cylinder(h=5, r=2.5, center=true);
-                translate([holder_size[0]-(holder_size[1]-tray_size[1])/2, holder_size[1]-(holder_size[1]-tray_size[1])/2, 0]) cylinder(h=5, r=2.5, center=true);
+            translate([(holder_pillar_size)/2, -holder_pillar_spacing-(holder_pillar_size)/2, holder_size[2]+stud_size[0]/2]) {
+                
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
+                
+                translate([holder_size[0]-(holder_pillar_size)/2-2*stud_size[1], 0, 0])
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
+                
+                translate([0, holder_size[1]-(holder_pillar_size), 0])
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
+                
+                translate([holder_size[0]-(holder_pillar_size)/2-2*stud_size[1], holder_size[1]-(holder_pillar_size), 0])
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
             }
             
         }
         union() {
             tray();
-            translate([(holder_size[1]-tray_size[1])/4-5.01, -(holder_size[1]-tray_size[1])/4, -0.501]) {
-                                                                                                                               cylinder(h=5, r=2.5, center=true);
-                translate([holder_size[0]-(holder_size[1]-tray_size[1])/2, 0, 0])                                              cylinder(h=5, r=2.5, center=true);
-                translate([0, holder_size[1]-(holder_size[1]-tray_size[1])/2, 0])                                              cylinder(h=5, r=2.5, center=true);
-                translate([holder_size[0]-(holder_size[1]-tray_size[1])/2, holder_size[1]-(holder_size[1]-tray_size[1])/2, 0]) cylinder(h=5, r=2.5, center=true);
+
+            // stud holes
+            translate([(holder_pillar_size)/2-5.01, -holder_pillar_spacing-(holder_pillar_size)/2, -0.51]) {
+                
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
+                
+                translate([holder_size[0]-(holder_pillar_size)/2-2*stud_size[1], 0,                                                               0])
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
+                
+                translate([0, holder_size[1]-(holder_pillar_size), 0])
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
+                
+                translate([holder_size[0]-(holder_pillar_size)/2-2*stud_size[1], holder_size[1]-(holder_pillar_size), 0])
+                    cylinder(h=stud_size[0], r=stud_size[1], center=true);
             }
         }