diff --git a/io_mesh_qfmdl_blubs/__init__.py b/io_mesh_qfmdl_blubs/__init__.py
index 29795ae..3e8b741 100644
--- a/io_mesh_qfmdl_blubs/__init__.py
+++ b/io_mesh_qfmdl_blubs/__init__.py
@@ -179,6 +179,11 @@ class QFMDLSettings(bpy.types.PropertyGroup):
         items=EFFECTS,
         name="Effects",
         description="Particle trail effects")
+    custom_flags : StringProperty(
+        name="Flags",
+        description="Int representing effect bitflags to write. If specified, Effects / Rotate flag values are ignored.",
+        default=""
+    )
 
     #doesn't work :(
     #script = PointerProperty(
@@ -283,6 +288,11 @@ class ExportMDL6(bpy.types.Operator, ExportHelper):
         items=EFFECTS,
         name="Effects",
         description="Particle trail effects")
+    custom_flags : StringProperty(
+        name="Flags",
+        description="Int representing effect bitflags to write. If specified, Effects / Rotate flag values are ignored.",
+        default=""
+    )
     xform : BoolProperty(
         name="Auto transform",
         description="Auto-apply location/rotation/scale when exporting",
@@ -362,6 +372,7 @@ class OBJECT_PT_MDLPanel(bpy.types.Panel):
         layout.prop(obj.qfmdl, "synctype")
         layout.prop(obj.qfmdl, "rotate")
         layout.prop(obj.qfmdl, "effects")
+        layout.prop(obj.qfmdl, "custom_flags")
         # layout.prop(obj.qfmdl, "script")
         layout.prop(obj.qfmdl, "xform")
         layout.prop(obj.qfmdl, "md16")
diff --git a/io_mesh_qfmdl_blubs/export_mdl.py b/io_mesh_qfmdl_blubs/export_mdl.py
index bdf3565..5df6163 100644
--- a/io_mesh_qfmdl_blubs/export_mdl.py
+++ b/io_mesh_qfmdl_blubs/export_mdl.py
@@ -245,6 +245,7 @@ def get_properties(
             synctype,
             rotate,
             effects,
+            custom_flags,
             xform,
             md16,
             mdl_first_frame,
@@ -257,6 +258,15 @@ def get_properties(
     mdl.synctype = MDL.SYNCTYPE[synctype]
     mdl.flags = ((rotate and MDL.EF_ROTATE or 0)
                  | MDL.EFFECTS[effects])
+    
+    # If custom_flags specified, try parsing as int
+    # If int is successfully parsed, replace flags / effects with it.
+    try:
+        custom_flags = int(custom_flags)
+        mdl.flags = custom_flags
+    except:
+        pass
+
     if md16:
         mdl.ident = "MD16"
 
@@ -358,6 +368,7 @@ def export_mdl(
     synctype = SYNCTYPE[1],
     rotate = False,
     effects = EFFECTS[1],
+    custom_flags='',
     xform = True,
     md16 = False,
     mdl_first_frame=0,
@@ -386,6 +397,7 @@ def export_mdl(
             synctype,
             rotate,
             effects,
+            custom_flags,
             xform,
             md16,
             mdl_first_frame,