diff --git a/mozglue/misc/AwakeTimeStamp.h b/mozglue/misc/AwakeTimeStamp.h
index e38405beab9c..6c6a358fbe33 100644
--- a/mozglue/misc/AwakeTimeStamp.h
+++ b/mozglue/misc/AwakeTimeStamp.h
@@ -30,6 +30,7 @@ class AwakeTimeDuration;
 // methods are equivalent on non-Windows.
 class AwakeTimeStamp {
  public:
+  using DurationType = AwakeTimeDuration;
   MFBT_API static AwakeTimeStamp NowLoRes();
   MFBT_API static AwakeTimeStamp Now();
   MFBT_API void operator+=(const AwakeTimeDuration& aOther);
diff --git a/mozglue/misc/TimeStamp.h b/mozglue/misc/TimeStamp.h
index 635b62cf1378..81e7515a9567 100644
--- a/mozglue/misc/TimeStamp.h
+++ b/mozglue/misc/TimeStamp.h
@@ -387,6 +387,7 @@ static_assert(sizeof(TimeStampValue) > 8);
  */
 class TimeStamp {
  public:
+  using DurationType = TimeDuration;
   /**
    * Initialize to the "null" moment
    */