Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/Ring.cs
===================================================================
diff -u -r228ee54da56eded41bf81bba88cf54371f11d2bb -r33a3c76cadc26935657a67c5b0d3e19733d84860
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/Ring.cs	(.../Ring.cs)	(revision 228ee54da56eded41bf81bba88cf54371f11d2bb)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/Ring.cs	(.../Ring.cs)	(revision 33a3c76cadc26935657a67c5b0d3e19733d84860)
@@ -22,6 +22,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using Core.Common.Base.Data;
 using Core.Common.Base.Geometry;
 
 namespace Ringtoets.MacroStabilityInwards.Primitives
@@ -43,10 +44,13 @@
         public Ring(IEnumerable<Point2D> points)
         {
             ValidateAndTrimPoints(points);
-            Points = points.ToArray();
+            Points = new RoundedPoint2DCollection(2, points);
         }
 
-        public IEnumerable<Point2D> Points { get; }
+        /// <summary>
+        /// Gets the points that form the ring.
+        /// </summary>
+        public RoundedPoint2DCollection Points { get; }
 
         public override bool Equals(object obj)
         {
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Primitives.Test/RingTest.cs
===================================================================
diff -u -rba648c3ed8287decc7600bac7e077df25fc7b57c -r33a3c76cadc26935657a67c5b0d3e19733d84860
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Primitives.Test/RingTest.cs	(.../RingTest.cs)	(revision ba648c3ed8287decc7600bac7e077df25fc7b57c)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Primitives.Test/RingTest.cs	(.../RingTest.cs)	(revision 33a3c76cadc26935657a67c5b0d3e19733d84860)
@@ -23,6 +23,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using Core.Common.Base.Geometry;
+using Core.Common.Base.TestUtil.Geometry;
 using Core.Common.TestUtil;
 using NUnit.Framework;
 
@@ -55,23 +56,22 @@
         }
 
         [Test]
-        public void Constructor_WithValidPointsArray_PointSetCopiedToNewCollection()
+        public void Constructor_WithPoints_ExpectedValues()
         {
             // Setup
             var points = new[]
             {
-                new Point2D(3, 2),
-                new Point2D(5, 6),
-                new Point2D(1, 1.2)
+                new Point2D(3.0, 2.001),
+                new Point2D(5.436, 6.4937),
+                new Point2D(1, 1.23)
             };
 
-            var ring = new Ring(points);
-
             // Call
-            IEnumerable<Point2D> ringPoints = ring.Points;
-
+            var ring = new Ring(points);
+            
             // Assert
-            TestHelper.AssertAreEqualButNotSame(points, ringPoints);
+            Assert.AreEqual(2, ring.Points.NumberOfDecimalPlaces);
+            CollectionAssert.AreEqual(points, ring.Points, new Point2DComparerWithTolerance(1e-2));
         }
 
         [TestFixture]
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Primitives.Test/Ringtoets.MacroStabilityInwards.Primitives.Test.csproj
===================================================================
diff -u -rac96d7c315129af851634ed5a4a6800b59ede718 -r33a3c76cadc26935657a67c5b0d3e19733d84860
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Primitives.Test/Ringtoets.MacroStabilityInwards.Primitives.Test.csproj	(.../Ringtoets.MacroStabilityInwards.Primitives.Test.csproj)	(revision ac96d7c315129af851634ed5a4a6800b59ede718)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Primitives.Test/Ringtoets.MacroStabilityInwards.Primitives.Test.csproj	(.../Ringtoets.MacroStabilityInwards.Primitives.Test.csproj)	(revision 33a3c76cadc26935657a67c5b0d3e19733d84860)
@@ -42,6 +42,10 @@
       <Project>{F49BD8B2-332A-4C91-A196-8CCE0A2C7D98}</Project>
       <Name>Core.Common.Util</Name>
     </ProjectReference>
+    <ProjectReference Include="..\..\..\..\Core\Common\test\Core.Common.Base.TestUtil\Core.Common.Base.TestUtil.csproj">
+      <Project>{8E2FAB92-51AA-47B0-B18A-9AC0455EF77D}</Project>
+      <Name>Core.Common.Base.TestUtil</Name>
+    </ProjectReference>
     <ProjectReference Include="..\..\..\..\Core\Common\test\Core.Common.TestUtil\Core.Common.TestUtil.csproj">
       <Project>{D749EE4C-CE50-4C17-BF01-9A953028C126}</Project>
       <Name>Core.Common.TestUtil</Name>