diff --git a/Compression/MSZIP/Block.cs b/Compression/MSZIP/Block.cs
new file mode 100644
index 0000000..3a36f93
--- /dev/null
+++ b/Compression/MSZIP/Block.cs
@@ -0,0 +1,41 @@
+namespace SabreTools.Models.Compression.MSZIP
+{
+    /// <summary>
+    /// Each MSZIP block MUST consist of a 2-byte MSZIP signature and one or more RFC 1951 blocks. The
+    /// 2-byte MSZIP signature MUST consist of the bytes 0x43 and 0x4B. The MSZIP signature MUST be
+    /// the first 2 bytes in the MSZIP block. The MSZIP signature is shown in the following packet diagram.
+    /// 
+    /// Each MSZIP block is the result of a single deflate compression operation, as defined in [RFC1951].
+    /// The compressor that performs the compression operation MUST generate one or more RFC 1951
+    /// blocks, as defined in [RFC1951]. The number, deflation mode, and type of RFC 1951 blocks in each
+    /// MSZIP block is determined by the compressor, as defined in [RFC1951]. The last RFC 1951 block in
+    /// each MSZIP block MUST be marked as the "end" of the stream(1), as defined by [RFC1951]
+    /// section 3.2.3. Decoding trees MUST be discarded after each RFC 1951 block, but the history buffer
+    /// MUST be maintained.Each MSZIP block MUST represent no more than 32 KB of uncompressed data.
+    /// 
+    /// The maximum compressed size of each MSZIP block is 32 KB + 12 bytes. This enables the MSZIP
+    /// block to contain 32 KB of data split between two noncompressed RFC 1951 blocks, each of which
+    /// has a value of BTYPE = 00.
+    /// </summary>
+    /// <see href="https://interoperability.blob.core.windows.net/files/MS-MCI/%5bMS-MCI%5d.pdf"/>
+    public class Block
+    {
+        /// <summary>
+        /// Block header
+        /// </summary>
+#if NET48
+        public BlockHeader BlockHeader { get; set; }
+#else
+        public BlockHeader? BlockHeader { get; set; }
+#endif
+
+        /// <summary>
+        /// Compressed blocks
+        /// </summary>
+#if NET48
+        public RFC1951Block CompressedBlocks { get; set; }
+#else
+        public RFC1951Block? CompressedBlocks { get; set; }
+#endif
+    }
+}
\ No newline at end of file
diff --git a/Compression/MSZIP/BlockHeader.cs b/Compression/MSZIP/BlockHeader.cs
index 0336aec..657fcbc 100644
--- a/Compression/MSZIP/BlockHeader.cs
+++ b/Compression/MSZIP/BlockHeader.cs
@@ -4,18 +4,6 @@ namespace SabreTools.Models.Compression.MSZIP
     /// Each MSZIP block MUST consist of a 2-byte MSZIP signature and one or more RFC 1951 blocks. The
     /// 2-byte MSZIP signature MUST consist of the bytes 0x43 and 0x4B. The MSZIP signature MUST be
     /// the first 2 bytes in the MSZIP block. The MSZIP signature is shown in the following packet diagram.
-    /// 
-    /// Each MSZIP block is the result of a single deflate compression operation, as defined in [RFC1951].
-    /// The compressor that performs the compression operation MUST generate one or more RFC 1951
-    /// blocks, as defined in [RFC1951]. The number, deflation mode, and type of RFC 1951 blocks in each
-    /// MSZIP block is determined by the compressor, as defined in [RFC1951]. The last RFC 1951 block in
-    /// each MSZIP block MUST be marked as the "end" of the stream(1), as defined by [RFC1951]
-    /// section 3.2.3. Decoding trees MUST be discarded after each RFC 1951 block, but the history buffer
-    /// MUST be maintained.Each MSZIP block MUST represent no more than 32 KB of uncompressed data.
-    /// 
-    /// The maximum compressed size of each MSZIP block is 32 KB + 12 bytes. This enables the MSZIP
-    /// block to contain 32 KB of data split between two noncompressed RFC 1951 blocks, each of which
-    /// has a value of BTYPE = 00.
     /// </summary>
     /// <see href="https://interoperability.blob.core.windows.net/files/MS-MCI/%5bMS-MCI%5d.pdf"/>
     public class BlockHeader
diff --git a/Compression/MSZIP/CompressedBlockHeader.cs b/Compression/MSZIP/CompressedBlockHeader.cs
new file mode 100644
index 0000000..cb1fc6d
--- /dev/null
+++ b/Compression/MSZIP/CompressedBlockHeader.cs
@@ -0,0 +1,28 @@
+namespace SabreTools.Models.Compression.MSZIP
+{
+    /// <summary>
+    /// Compression with Huffman codes (BTYPE=01 or BTYPE=02)
+    /// </summary>
+    /// <see href="https://interoperability.blob.core.windows.net/files/MS-MCI/%5bMS-MCI%5d.pdf"/>
+    /// <see href="https://www.rfc-editor.org/rfc/rfc1951"/>
+    public abstract class CompressedBlockHeader
+    {
+        /// <summary>
+        /// Huffman code lengths for the literal / length alphabet
+        /// </summary>
+#if NET48
+        public virtual uint[] LiteralLengths { get; set; }
+#else
+        public virtual uint[]? LiteralLengths { get; set; }
+#endif
+
+        /// <summary>
+        /// Huffman distance codes for the literal / length alphabet
+        /// </summary>
+#if NET48
+        public virtual uint[] DistanceCodes { get; set; }
+#else
+        public virtual uint[]? DistanceCodes { get; set; }
+#endif
+    }
+}
\ No newline at end of file
diff --git a/Compression/MSZIP/DynamicHuffmanCompressedBlockHeader.cs b/Compression/MSZIP/DynamicHuffmanCompressedBlockHeader.cs
index e398ab0..14c3838 100644
--- a/Compression/MSZIP/DynamicHuffmanCompressedBlockHeader.cs
+++ b/Compression/MSZIP/DynamicHuffmanCompressedBlockHeader.cs
@@ -4,24 +4,8 @@ namespace SabreTools.Models.Compression.MSZIP
     /// Compression with dynamic Huffman codes (BTYPE=10)
     /// </summary>
     /// <see href="https://www.rfc-editor.org/rfc/rfc1951"/>
-    public class DynamicHuffmanCompressedBlockHeader
+    public class DynamicHuffmanCompressedBlockHeader : CompressedBlockHeader
     {
-        /// <summary>
-        /// Huffman code lengths for the literal / length alphabet
-        /// </summary>
-#if NET48
-        public int[] LiteralLengths { get; set; }
-#else
-        public int[]? LiteralLengths { get; set; }
-#endif
-
-        /// <summary>
-        /// Huffman distance codes for the literal / length alphabet
-        /// </summary>
-#if NET48
-        public int[] DistanceCodes { get; set; }
-#else
-        public int[]? DistanceCodes { get; set; }
-#endif
+        // Codes are provided externally
     }
 }
\ No newline at end of file
diff --git a/Compression/MSZIP/FixedHuffmanCompressedBlockHeader.cs b/Compression/MSZIP/FixedHuffmanCompressedBlockHeader.cs
index 27b7dc4..69f901d 100644
--- a/Compression/MSZIP/FixedHuffmanCompressedBlockHeader.cs
+++ b/Compression/MSZIP/FixedHuffmanCompressedBlockHeader.cs
@@ -7,7 +7,7 @@ namespace SabreTools.Models.Compression.MSZIP
     /// </summary>
     /// <see href="https://interoperability.blob.core.windows.net/files/MS-MCI/%5bMS-MCI%5d.pdf"/>
     /// <see href="https://www.rfc-editor.org/rfc/rfc1951"/>
-    public class FixedHuffmanCompressedBlockHeader
+    public class FixedHuffmanCompressedBlockHeader : CompressedBlockHeader
     {
         #region Properties
 
@@ -15,9 +15,9 @@ namespace SabreTools.Models.Compression.MSZIP
         /// Huffman code lengths for the literal / length alphabet
         /// </summary>
 #if NET48
-        public uint[] LiteralLengths
+        public override uint[] LiteralLengths
 #else
-        public uint[]? LiteralLengths
+        public override uint[]? LiteralLengths
 #endif
         {
             get
@@ -57,9 +57,9 @@ namespace SabreTools.Models.Compression.MSZIP
         /// Huffman distance codes for the literal / length alphabet
         /// </summary>
 #if NET48
-        public uint[] DistanceCodes
+        public override uint[] DistanceCodes
 #else
-        public uint[]? DistanceCodes
+        public override uint[]? DistanceCodes
 #endif
         {
             get
diff --git a/Compression/MSZIP/RFC1951Block.cs b/Compression/MSZIP/RFC1951Block.cs
new file mode 100644
index 0000000..817b618
--- /dev/null
+++ b/Compression/MSZIP/RFC1951Block.cs
@@ -0,0 +1,24 @@
+namespace SabreTools.Models.Compression.MSZIP
+{
+    /// <summary>
+    /// Each MSZIP block is the result of a single deflate compression operation, as defined in [RFC1951].
+    /// The compressor that performs the compression operation MUST generate one or more RFC 1951
+    /// blocks, as defined in [RFC1951]. The number, deflation mode, and type of RFC 1951 blocks in each
+    /// MSZIP block is determined by the compressor, as defined in [RFC1951]. The last RFC 1951 block in
+    /// each MSZIP block MUST be marked as the "end" of the stream(1), as defined by [RFC1951]
+    /// section 3.2.3. Decoding trees MUST be discarded after each RFC 1951 block, but the history buffer
+    /// MUST be maintained.Each MSZIP block MUST represent no more than 32 KB of uncompressed data.
+    /// </summary>
+    /// <see href="https://interoperability.blob.core.windows.net/files/MS-MCI/%5bMS-MCI%5d.pdf"/>
+    public class RFC1951Block
+    {
+        /// <summary>
+        /// Compressed MSZIP data block
+        /// </summary>
+#if NET48
+        public byte[] Data { get; set; }
+#else
+        public byte[]? Data { get; set; }
+#endif
+    }
+}
\ No newline at end of file