diff --git a/SerialPortRx/ISerialPortRx.cs b/SerialPortRx/ISerialPortRx.cs
index 41dcaac..1df3e76 100644
--- a/SerialPortRx/ISerialPortRx.cs
+++ b/SerialPortRx/ISerialPortRx.cs
@@ -49,7 +49,13 @@ public interface ISerialPortRx : IDisposable
         /// Gets the is open.
         /// </summary>
         /// <value>The is open.</value>
-        IReadOnlyReactiveProperty<bool> IsOpen { get; }
+        bool IsOpen { get; }
+
+        /// <summary>
+        /// Gets the is open observable.
+        /// </summary>
+        /// <value>The is open observable.</value>
+        IObservable<bool> IsOpenObservable { get; }
 
         /// <summary>
         /// Gets or sets the parity.
diff --git a/SerialPortRx/Properties/AssemblyInfo.cs b/SerialPortRx/Properties/AssemblyInfo.cs
index 682937a..ef9a045 100644
--- a/SerialPortRx/Properties/AssemblyInfo.cs
+++ b/SerialPortRx/Properties/AssemblyInfo.cs
@@ -3,7 +3,7 @@
 
 [assembly: AssemblyTitle("SerialPortRx")]
 [assembly: AssemblyDescription("An Observable Com port extension of System.IO.Ports.SerialPort")]
-[assembly: AssemblyConfiguration(".Net 4.7.1")]
+[assembly: AssemblyConfiguration(".Net 4.6.1")]
 [assembly: AssemblyCompany("ChrisPulman")]
 [assembly: AssemblyProduct("SerialPortRx")]
 [assembly: AssemblyCopyright("Copyright © https://github.com/ChrisPulman 2018")]
@@ -11,5 +11,5 @@
 [assembly: AssemblyCulture("")]
 [assembly: ComVisible(false)]
 [assembly: Guid("cda3585b-d3d6-4be4-9a6b-582ab5de0b8f")]
-[assembly: AssemblyVersion("1.2.0")]
-[assembly: AssemblyFileVersion("1.2.0")]
+[assembly: AssemblyVersion("1.3.0")]
+[assembly: AssemblyFileVersion("1.3.0")]
diff --git a/SerialPortRx/SerialPortRx.cs b/SerialPortRx/SerialPortRx.cs
index 8f84097..819e40a 100644
--- a/SerialPortRx/SerialPortRx.cs
+++ b/SerialPortRx/SerialPortRx.cs
@@ -202,7 +202,13 @@ public SerialPortRx()
         /// <value>The is open.</value>
         [Browsable(true)]
         [MonitoringDescription("IsOpen")]
-        public IReadOnlyReactiveProperty<bool> IsOpen => isOpen.ToReadOnlyReactiveProperty();
+        public bool IsOpen => isOpen.Value;
+
+        /// <summary>
+        /// Gets the is open observable.
+        /// </summary>
+        /// <value>The is open observable.</value>
+        public IObservable<bool> IsOpenObservable => Observable.Create<bool>(obs => isOpen.Subscribe(obs));
 
         /// <summary>
         /// Gets or sets the parity.
@@ -309,7 +315,7 @@ from data in port.ReadExisting()
             });
         }).OnErrorRetry((Exception ex) => errors.OnNext(ex)).Publish().RefCount();
 
-        private IReactiveProperty<bool> isOpen { get; } = new ReactiveProperty<bool>();
+        internal IReactiveProperty<bool> isOpen { get; } = new ReactiveProperty<bool>();
 
         /// <summary>
         /// Closes this instance.
diff --git a/SerialPortRx/SerialPortRx.csproj b/SerialPortRx/SerialPortRx.csproj
index bfb314b..3b9deb6 100644
--- a/SerialPortRx/SerialPortRx.csproj
+++ b/SerialPortRx/SerialPortRx.csproj
@@ -9,7 +9,7 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>CP.IO.Ports</RootNamespace>
     <AssemblyName>SerialPortRx</AssemblyName>
-    <TargetFrameworkVersion>v4.7.1</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.6.1</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <TargetFrameworkProfile />
   </PropertyGroup>
@@ -35,6 +35,9 @@
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <DocumentationFile>bin\Release\SerialPortRx.XML</DocumentationFile>
   </PropertyGroup>
+  <PropertyGroup>
+    <AutoGenerateBindingRedirects>true</AutoGenerateBindingRedirects>
+  </PropertyGroup>
   <ItemGroup>
     <Compile Include="ISerialPortRx.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
@@ -58,7 +61,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="RxProperty">
-      <Version>5.3.0</Version>
+      <Version>5.3.2</Version>
     </PackageReference>
   </ItemGroup>
   <ItemGroup>
diff --git a/SerialPortRx/SerialPortRx.nuspec b/SerialPortRx/SerialPortRx.nuspec
index 73bbf50..f366f50 100644
--- a/SerialPortRx/SerialPortRx.nuspec
+++ b/SerialPortRx/SerialPortRx.nuspec
@@ -12,10 +12,10 @@
     <copyright>Copyright © $author$ 2018</copyright>
     <projectUrl>https://github.com/chrispulman/SerialPortRx</projectUrl>
     <dependencies>
-      <dependency id="RxProperty" version="5.3.0" />
+      <dependency id="RxProperty" version="5.3.2" />
     </dependencies>
   </metadata>
   <files>
-    <file src="bin\$configuration$\$id$.pdb" target="lib\net471\" />
+    <file src="bin\$configuration$\$id$.pdb" target="lib\net461\" />
   </files>
 </package>
\ No newline at end of file
diff --git a/SerialPortRx/SerialPortRxMixins.cs b/SerialPortRx/SerialPortRxMixins.cs
index 457bdb2..030344a 100644
--- a/SerialPortRx/SerialPortRxMixins.cs
+++ b/SerialPortRx/SerialPortRxMixins.cs
@@ -261,7 +261,7 @@ public static IObservable<TSource> OnErrorRetry<TSource, TException>(this IObser
         /// <returns></returns>
         public static IObservable<bool> WhileIsOpen(this SerialPortRx @this, TimeSpan timespan) =>
             Observable.Defer(() => Observable.Create<bool>(obs => {
-                var isOpen = Observable.Interval(timespan).CombineLatest(@this.IsOpen.DistinctUntilChanged(), (a, b) => b).Where(x => x);
+                var isOpen = Observable.Interval(timespan).CombineLatest(@this.isOpen, (a, b) => b).Where(x => x);
                 return isOpen.Subscribe(obs);
             }));
     }