diff --git a/src/ess/reduce/nexus/types.py b/src/ess/reduce/nexus/types.py
index 4ec6ef15..4f559f55 100644
--- a/src/ess/reduce/nexus/types.py
+++ b/src/ess/reduce/nexus/types.py
@@ -91,6 +91,8 @@ class TransmissionRun(Generic[ScatteringRunType]):
 """Identifier for an arbitrary monitor"""
 Monitor5 = NewType('Monitor5', int)
 """Identifier for an arbitrary monitor"""
+Monitor6 = NewType('Monitor6', int)
+"""Identifier for an arbitrary monitor"""
 IncidentMonitor = NewType('IncidentMonitor', int)
 """Incident monitor"""
 TransmissionMonitor = NewType('TransmissionMonitor', int)
@@ -102,6 +104,7 @@ class TransmissionRun(Generic[ScatteringRunType]):
     Monitor3,
     Monitor4,
     Monitor5,
+    Monitor6,
     IncidentMonitor,
     TransmissionMonitor,
 )
@@ -119,6 +122,7 @@ class TransmissionRun(Generic[ScatteringRunType]):
     Monitor3,
     Monitor4,
     Monitor5,
+    Monitor6,
     IncidentMonitor,
     TransmissionMonitor,
 )