diff --git a/compact/gem_tracker_endcap.xml b/compact/gem_tracker_endcap.xml
index 289e8cac4e60223450aae81180e94a6d67624f24..618b7d4124a190198e8e4a290a3850568337486f 100644
--- a/compact/gem_tracker_endcap.xml
+++ b/compact/gem_tracker_endcap.xml
@@ -105,6 +105,9 @@
         <trd x1="GEMTrackerEndcapFoilX2/2.0" x2="GEMTrackerEndcapFoilX1/2.0" z="GEMTrackerEndcapFrameBotEdge_width"/>
         <module_component thickness="GEMTrackerEndcapFrame_thickness" material="Mylar"/>
       </module>
+      <comment>
+        GEMSupportModule2 is the support in between gem foils.
+      </comment>
       <module name="GEMSupportModule2" vis="OrangeVis">
         <trd x1="GEMTrackerEndcapFrameSideEdge_width" x2="GEMTrackerEndcapFrameSideEdge_width" z="GEMTrackerEndcapFoilY/2"/>
         <module_component thickness="4.0*mm" material="Mylar"/>
diff --git a/gem_tracker.xml b/gem_tracker.xml
index fac424157c2bae962dba0d389fd3e5d2405c7494..f0e59801023f93ea34b755a41d4decb02f1c546a 100644
--- a/gem_tracker.xml
+++ b/gem_tracker.xml
@@ -14,10 +14,10 @@
   </includes>
   
   <define>
-    <constant name="world_side" value="10*m"/>
+    <constant name="world_side" value="5*m"/>
     <constant name="world_x" value="world_side"/>
     <constant name="world_y" value="world_side"/>
-    <constant name="world_z" value="10*world_side"/>
+    <constant name="world_z" value="world_side"/>
     
     <constant name="tracker_region_rmax" value="2.0*m" />
     <constant name="tracker_region_zmax" value="4.0*m" />
@@ -71,7 +71,7 @@
     <vis name="GrayVis"        alpha="1.0"  r= "0.75" g="0.75" b="0.75" showDaughters="true" visible="true"/>
   </display>
 
-  <include ref="compact/gem_tracker_endcap.xml"/>
+  <!--include ref="compact/gem_tracker_endcap.xml"/-->
 
   <detectors>
 
diff --git a/src/GEMTrackerDisc_geo.cpp b/src/GEMTrackerDisc_geo.cpp
index df8aeb5b1f0354e2cc1ddcc10a5edca9e6df24d8..2bcdbbe168edaed0d7c7f707f223c14cfcffcbed 100644
--- a/src/GEMTrackerDisc_geo.cpp
+++ b/src/GEMTrackerDisc_geo.cpp
@@ -39,9 +39,6 @@ static Ref_t create_detector(Detector& lcdd, xml_h e, SensitiveDetector sens)
 
   DetElement  sdet(det_name, det_id);
   Assembly    assembly(det_name+"_assembly");
-  //Acts::ActsExtension* ecapDetExt = new Acts::ActsExtension();
-  //ecapDetExt->addType("barrel", "detector");
-  //sdet.addExtension<Acts::ActsExtension>(ecapDetExt);
 
   sens.setType("tracker");
   string module_name = "GEM";
@@ -64,37 +61,17 @@ static Ref_t create_detector(Detector& lcdd, xml_h e, SensitiveDetector sens)
     Tube    gem_layer(inner_r, outer_r, thickness/2.0);
     Volume  gem_layer_vol("gem_layer_vol", gem_layer, carbon);
 
-    // DD4hep surfaces
-    //Vector3D u( 1. , 0. , 0. ) ;
-    //Vector3D v( 0. , 1. , 0. ) ;
-    //Vector3D n( 0. , 0. , 1. ) ;
-    //Vector3D o( 0. , 0. , 0. ) ;
-    //double inner_thickness = thickness/2.0;
-    //double outer_thickness = thickness/2.0;
-    //SurfaceType type( SurfaceType::Sensitive ) ;
-    //VolPlane    surf( gem_layer_vol, type, inner_thickness , outer_thickness , u,v,n,o ) ;
-
     gem_layer_vol.setSensitiveDetector(sens);
 
     DetElement layer_DE( sdet, _toString(layer_id,"layer%d"), layer_id );
 
-    //Acts::ActsExtension* detlayer = new Acts::ActsExtension();
-    //detlayer->addType("sensitive disk", "layer");
-    // the local coordinate systems of modules in dd4hep and acts differ
-    // see http://acts.web.cern.ch/ACTS/latest/doc/group__DD4hepPlugins.html
-    //detlayer->addType("axes", "definitions", "XYZ");
-    //layer_DE.addExtension<Acts::ActsExtension>(detlayer);
-
-    //Assembly   layer_assembly( layer_name+"_assembly" );
     pv = assembly.placeVolume( gem_layer_vol, Transform3D(RotationZ(phi0_offset),Position(0.0,0.0,z)) );
     pv.addPhysVolID( "layer", layer_id );
     layer_DE.setPlacement(pv);
-    //layer_DE.setAttributes(lcdd, layer_assembly, "", "", "SiVertexLayerVis");
 
   }
 
   sdet.setAttributes(lcdd, assembly,x_det.regionStr(),x_det.limitsStr(),x_det.visStr());
-  //assembly.setVisAttributes(lcdd.invisible());
 
   pv = lcdd.pickMotherVolume(sdet).placeVolume(assembly);
   pv.addPhysVolID("system", det_id);      // Set the subdetector system ID.