diff --git a/compact/materials.xml b/compact/materials.xml
index d21627f1ebddfb6853b96ad61af2ef4c48ed4019..d6c3e5208d55ab8b0ae79e5891102d5349a72310 100644
--- a/compact/materials.xml
+++ b/compact/materials.xml
@@ -97,6 +97,13 @@
     <fraction n="0.040" ref="SodiumOxide"/>
     <fraction n="0.023" ref="AluminumOxide"/>
   </material>
+  <material name="PyrexGlass25">
+    <D type="density" value="0.5575" unit="g/cm3"/>
+    <fraction n="0.806" ref="SiliconOxide"/>
+    <fraction n="0.130" ref="BoronOxide"/>
+    <fraction n="0.040" ref="SodiumOxide"/>
+    <fraction n="0.023" ref="AluminumOxide"/>
+  </material>
   <material name="PbGlass">
     <D type="density" value="3.86" unit="g / cm3"/>
     <fraction n="0.5080" ref="LeadOxide"/>
diff --git a/compact/mrich.xml b/compact/mrich.xml
index 469952a1e95ebb25d25122d50228bfdec436b2f8..cfccfcc5dd3d7a3c2ddda34459cf7fb117300025 100644
--- a/compact/mrich.xml
+++ b/compact/mrich.xml
@@ -15,10 +15,13 @@
     <constant name="MRICHPhotoDet_thickness"          value="1.5*mm"/>
     <constant name="MRICHPhotoDet_length"             value="48.5*mm"/>
     <constant name="MRICHGlassWindow_width"           value="103.5*mm"/>
-    <constant name="MRICHGlassPhotoDet_thickness"     value="2.0*mm"/>
+    <constant name="MRICHGlassPhotoDet_thickness"     value="5.0*mm"/>
+    <constant name="MRICHPhotoDetMCPlate_thickness"   value="0.3*mm"/> <!-- FIXME: should be 1.2*mm with PyrexGlass25 -->
+    <constant name="MRICHPhotoDetAnode_thickness"     value="3.8*mm"/>
+    <constant name="MRICHPhotoDetPCB_thickness"       value="2.0*mm"/>
     <constant name="MRICHPhotoDetCopper_thickness"    value="0.1*mm"/>
     <constant name="MRICHPhotoDetKapton_thickness"    value="0.2*mm"/>
-    <constant name="MRICHRearExtraSpace_thickness"    value="9.7*mm"/>
+    <constant name="MRICHRearExtraSpace_thickness"    value="0.3*mm"/>
     <constant name="MRICHLensPhotoDet_length"         value="136.4*mm"/>
     <constant name="MRICHMirror_thickness"            value="2.0*mm"/>
     <constant name="MRICHMirror_length"               value="MRICHLensPhotoDet_length - MRICHLensMirrorGap_thickness"/>
@@ -42,6 +45,9 @@
       + MRICHFresnelLens_thickness
       + MRICHLensPhotoDet_length
       + MRICHGlassPhotoDet_thickness
+      + 2.0*MRICHPhotoDetMCPlate_thickness
+      + MRICHPhotoDetAnode_thickness
+      + MRICHPhotoDetPCB_thickness
       + MRICHPhotoDetCopper_thickness
       + MRICHPhotoDetKapton_thickness
       + MRICHRearExtraSpace_thickness "/>
@@ -86,8 +92,12 @@
                 material="AluminumOxide"/>
         <photodet width="MRICHGlassWindow_width" thickness="MRICHGlassPhotoDet_thickness"  material="PyrexGlassOptical">
           <sensor nx="2" ny="2" thickness="MRICHPhotoDet_thickness" width="MRICHPhotoDet_length" material="SiliconOxide"/>
-          <!--layer thickness="MRICHPhotoDetCopper_thickness" material="Copper"/-->
-          <!--layer thickness="MRICHPhotoDetKapton_thickness" material="Kapton"/-->
+          <layer thickness="MRICHPhotoDetMCPlate_thickness" material="PyrexGlass"/> <!-- FIXME: should be PyrexGlass25 with 1.2*mm thickness -->
+          <layer thickness="MRICHPhotoDetMCPlate_thickness" material="PyrexGlass"/> <!-- FIXME: should be PyrexGlass25 with 1.2*mm thickness -->
+          <layer thickness="MRICHPhotoDetAnode_thickness"   material="AluminumOxide"/>
+          <layer thickness="MRICHPhotoDetPCB_thickness"     material="Fr4"/>
+          <layer thickness="MRICHPhotoDetCopper_thickness"  material="Copper"/>
+          <layer thickness="MRICHPhotoDetKapton_thickness"  material="Kapton"/>
         </photodet>
       </module>
       <comment>
diff --git a/src/MRich_geo.cpp b/src/MRich_geo.cpp
index 65954a1eaf72c9768b572d284fbeae7937af80e6..9eb0ff27dbb3559b0ec0d3b768f2392fc3ae910d 100644
--- a/src/MRich_geo.cpp
+++ b/src/MRich_geo.cpp
@@ -239,7 +239,7 @@ static Ref_t createDetector(Detector& description, xml::Handle_t e, SensitiveDet
   int     sensor_ny   = getAttrOrDefault(x_photodet_sensor, _Unicode(ny), 2);
 
   Box    window_box(photodet_width/2.0,photodet_width/2.0,photodet_thickness/2.0);
-  Volume           window_vol(mod_name+"_window", window_box, photodet_mat);
+  Volume window_vol(mod_name+"_window", window_box, photodet_mat);
   double window_zpos = mirror_zpos + mirror_length/2.0+photodet_thickness/2.0;
   pv = m_volume.placeVolume(window_vol,Position(0,0,window_zpos));
   DetElement   comp_de(mod_de, std::string("mod_sensor_de_") + std::to_string(1) ,  1);