diff --git a/topside/silicon_tracker.xml b/topside/silicon_tracker.xml
index 723292d60466431d72f950be500111435e834336..5c6a03e8d80a00c26bcfcc813996b820e26b5c5e 100644
--- a/topside/silicon_tracker.xml
+++ b/topside/silicon_tracker.xml
@@ -189,7 +189,7 @@
         <module_component width="SiliconTrackerBarrelMod2Width" length="SiliconTrackerBarrelMod2Length" thickness="0.016 * cm" material="CarbonFiber_50D" sensitive="false">
           <position z="0.0915 * cm"/>
         </module_component>
-        <module_component width="45 * mm" length="45 * mm" thickness="0.03 * cm" material="Silicon" sensitive="true">
+        <module_component width="SiliconTrackerBarrelMod2Width" length="SiliconTrackerBarrelMod2Length" thickness="0.03 * cm" material="Silicon" sensitive="true">
           <position z="0.1145 * cm"/>
         </module_component>
         <module_component width="SiliconTrackerBarrelMod2Width" length="SiliconTrackerBarrelMod2Length" thickness="0.00048 * cm" material="Silicon" sensitive="false">
@@ -219,7 +219,7 @@
         <module_component width="SiliconTrackerBarrelMod3Width" length="SiliconTrackerBarrelMod3Length" thickness="0.016 * cm" material="CarbonFiber_50D" sensitive="false">
           <position z="0.0915 * cm"/>
         </module_component>
-        <module_component width="45 * mm" length="45 * mm" thickness="0.03 * cm" material="Silicon" sensitive="true">
+        <module_component width="SiliconTrackerBarrelMod3Width" length="SiliconTrackerBarrelMod3Length" thickness="0.03 * cm" material="Silicon" sensitive="true">
           <position z="0.1145 * cm"/>
         </module_component>
         <module_component width="SiliconTrackerBarrelMod3Width" length="SiliconTrackerBarrelMod3Length" thickness="0.00048 * cm" material="Silicon" sensitive="false">
@@ -249,7 +249,7 @@
         <module_component width="SiliconTrackerBarrelMod4Width" length="SiliconTrackerBarrelMod4Length" thickness="0.016 * cm" material="CarbonFiber_50D" sensitive="false">
           <position z="0.0915 * cm"/>
         </module_component>
-        <module_component width="45 * mm" length="45 * mm" thickness="0.03 * cm" material="Silicon" sensitive="true">
+        <module_component width="SiliconTrackerBarrelMod4Width" length="SiliconTrackerBarrelMod4Length" thickness="0.03 * cm" material="Silicon" sensitive="true">
           <position z="0.1145 * cm"/>
         </module_component>
         <module_component width="SiliconTrackerBarrelMod4Width" length="SiliconTrackerBarrelMod4Length" thickness="0.00048 * cm" material="Silicon" sensitive="false">
@@ -279,7 +279,7 @@
         <module_component width="SiliconTrackerBarrelMod5Width" length="SiliconTrackerBarrelMod5Length" thickness="0.016 * cm" material="CarbonFiber_50D" sensitive="false">
           <position z="0.0915 * cm"/>
         </module_component>
-        <module_component width="45 * mm" length="45 * mm" thickness="0.03 * cm" material="Silicon" sensitive="true">
+        <module_component width="SiliconTrackerBarrelMod5Width" length="SiliconTrackerBarrelMod5Length" thickness="0.03 * cm" material="Silicon" sensitive="true">
           <position z="0.1145 * cm"/>
         </module_component>
         <module_component width="SiliconTrackerBarrelMod5Width" length="SiliconTrackerBarrelMod5Length" thickness="0.00048 * cm" material="Silicon" sensitive="false">