diff --git a/Tests/Cosmos.Compiler.Tests.Bcl/Kernel.cs b/Tests/Cosmos.Compiler.Tests.Bcl/Kernel.cs
index 8bb114a448..11509f711e 100644
--- a/Tests/Cosmos.Compiler.Tests.Bcl/Kernel.cs
+++ b/Tests/Cosmos.Compiler.Tests.Bcl/Kernel.cs
@@ -45,6 +45,7 @@ protected override void Run()
                 SingleTest.Execute();
                 DoubleTest.Execute();
                 MathTest.Execute();
+                ConvertTests.Execute();
 
                 //mDebugger.Send("Thread test start of 500 ms");
                 //ThreadTest.Execute();
diff --git a/Tests/Cosmos.Compiler.Tests.Bcl/System/ConvertTests.cs b/Tests/Cosmos.Compiler.Tests.Bcl/System/ConvertTests.cs
new file mode 100644
index 0000000000..656c30f79b
--- /dev/null
+++ b/Tests/Cosmos.Compiler.Tests.Bcl/System/ConvertTests.cs
@@ -0,0 +1,29 @@
+using System;
+
+using Cosmos.TestRunner;
+
+namespace Cosmos.Compiler.Tests.Bcl.System
+{
+    internal static class ConvertTests
+    {
+        public static void Execute()
+        {
+            var number = 5;
+            var numberToString = Convert.ToString(number);
+
+            Assert.IsTrue(numberToString == "5", $"Convert.ToString(Int32) doesn't work. Result: {numberToString}");
+
+            var numberToByte = Convert.ToByte(number);
+
+            Assert.IsTrue(numberToByte == 5, $"Convert.ToByte(Int32) doesn't work. Result: {numberToByte}");
+
+            var byteToSingle = Convert.ToSingle(numberToByte);
+
+            Assert.IsTrue(EqualityHelper.SinglesAreEqual(byteToSingle, 5.0f), $"Convert.ToSingle(Byte) doesn't work. Result: {byteToSingle}");
+            
+            var numberToBase64 = Convert.ToBase64String(BitConverter.GetBytes(number));
+
+            Assert.IsTrue(numberToBase64 == "BQAAAA==", $"Convert.ToBase64String(byte[]) doesn't work. Result: {numberToBase64}");
+        }
+    }
+}
diff --git a/source/Archive/Old System Plugs/DecimalImpl.cs b/source/Cosmos.System2_Plugs/System/DecimalImpl.cs
similarity index 70%
rename from source/Archive/Old System Plugs/DecimalImpl.cs
rename to source/Cosmos.System2_Plugs/System/DecimalImpl.cs
index 434744b466..9b452bed6b 100644
--- a/source/Archive/Old System Plugs/DecimalImpl.cs	
+++ b/source/Cosmos.System2_Plugs/System/DecimalImpl.cs
@@ -1,12 +1,8 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 
-using Cosmos.IL2CPU.Plugs;
+using IL2CPU.API.Attribs;
 
-namespace Cosmos.System.Plugs.System
+namespace Cosmos.System_Plugs.System
 {
     [Plug(Target = typeof(decimal))]
     public static class DecimalImpl
diff --git a/source/Cosmos.System2_Plugs/System/Int32Impl.cs b/source/Cosmos.System2_Plugs/System/Int32Impl.cs
index 76d8555151..be131cba90 100644
--- a/source/Cosmos.System2_Plugs/System/Int32Impl.cs
+++ b/source/Cosmos.System2_Plugs/System/Int32Impl.cs
@@ -1,7 +1,5 @@
 using System;
 using Cosmos.Common;
-using Cosmos.Debug.Kernel;
-using IL2CPU.API;
 using IL2CPU.API.Attribs;
 
 namespace Cosmos.System_Plugs.System
@@ -14,6 +12,8 @@ public static string ToString(ref int aThis)
             return StringHelper.GetNumberString(aThis);
         }
 
+        public static string ToString(ref int aThis, IFormatProvider aFormatProvider) => ToString(ref aThis);
+
         public static Int32 Parse(string s)
         {
             const string digits = "0123456789";