diff --git a/UnitsNet.Tests/CustomCode/MassTests.cs b/UnitsNet.Tests/CustomCode/MassTests.cs
index 285cb7a6ec..06b5da606c 100644
--- a/UnitsNet.Tests/CustomCode/MassTests.cs
+++ b/UnitsNet.Tests/CustomCode/MassTests.cs
@@ -90,6 +90,13 @@ public void MassDividedByTimeSpanEqualsMassFlow()
             Assert.Equal(massFlow, MassFlow.FromKilogramsPerSecond(3.0));
         }
 
+        [Fact]
+        public void MassDividedByMassFlowEqualsTimeSpan()
+        {
+            TimeSpan timeSpan = Mass.FromKilograms(20) / MassFlow.FromKilogramsPerSecond(2);
+            Assert.Equal(TimeSpan.FromSeconds(10), timeSpan);
+        }
+
         [Fact]
         public void MassDividedByVolumeEqualsDensity()
         {
diff --git a/UnitsNet/CustomCode/Quantities/Mass.extra.cs b/UnitsNet/CustomCode/Quantities/Mass.extra.cs
index e82862fc21..1673362b57 100644
--- a/UnitsNet/CustomCode/Quantities/Mass.extra.cs
+++ b/UnitsNet/CustomCode/Quantities/Mass.extra.cs
@@ -58,6 +58,12 @@ public static Mass FromStonePounds(double stone, double pounds)
             return MassFlow.FromKilogramsPerSecond(mass.Kilograms/duration.Seconds);
         }
 
+        /// <summary>Get <see cref="TimeSpan"/> from <see cref="Mass"/> divided by <see cref="MassFlow"/>.</summary>
+        public static TimeSpan operator /(Mass mass, MassFlow massFlow)
+        {
+            return TimeSpan.FromSeconds(mass.Kilograms/massFlow.KilogramsPerSecond);
+        }
+
         /// <summary>Get <see cref="Density"/> from <see cref="MassFlow"/> divided by <see cref="Volume"/>.</summary>
         public static Density operator /(Mass mass, Volume volume)
         {