diff --git a/core/src/main/java/com/bloxbean/cardano/yaci/core/model/ProtocolParamUpdate.java b/core/src/main/java/com/bloxbean/cardano/yaci/core/model/ProtocolParamUpdate.java
index 623bbd3..8685431 100644
--- a/core/src/main/java/com/bloxbean/cardano/yaci/core/model/ProtocolParamUpdate.java
+++ b/core/src/main/java/com/bloxbean/cardano/yaci/core/model/ProtocolParamUpdate.java
@@ -1,5 +1,6 @@
 package com.bloxbean.cardano.yaci.core.model;
 
+import com.bloxbean.cardano.yaci.core.util.Tuple;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import lombok.*;
 
@@ -28,7 +29,7 @@ public class ProtocolParamUpdate {
     private BigDecimal expansionRate; //unit interval //10
     private BigDecimal treasuryGrowthRate; //11
     private BigDecimal decentralisationParam; //12
-    private String extraEntropy; //TODO //13
+    private Tuple<Integer, String> extraEntropy; //13
     private Integer protocolMajorVer; //14
     private Integer protocolMinorVer; //14
     private BigInteger minUtxo; //TODO //15
diff --git a/core/src/main/java/com/bloxbean/cardano/yaci/core/model/serializers/UpdateSerializer.java b/core/src/main/java/com/bloxbean/cardano/yaci/core/model/serializers/UpdateSerializer.java
index f8bc91c..3bd32b1 100644
--- a/core/src/main/java/com/bloxbean/cardano/yaci/core/model/serializers/UpdateSerializer.java
+++ b/core/src/main/java/com/bloxbean/cardano/yaci/core/model/serializers/UpdateSerializer.java
@@ -2,12 +2,12 @@
 
 import co.nstant.in.cbor.model.*;
 import com.bloxbean.cardano.client.crypto.Blake2bUtil;
-import com.bloxbean.cardano.client.util.Tuple;
 import com.bloxbean.cardano.yaci.core.model.ProtocolParamUpdate;
 import com.bloxbean.cardano.yaci.core.model.Update;
 import com.bloxbean.cardano.yaci.core.protocol.Serializer;
 import com.bloxbean.cardano.yaci.core.util.CborSerializationUtil;
 import com.bloxbean.cardano.yaci.core.util.HexUtil;
+import com.bloxbean.cardano.yaci.core.util.Tuple;
 
 import java.math.BigDecimal;
 import java.math.BigInteger;
@@ -90,7 +90,7 @@ public ProtocolParamUpdate getProtocolParams(Map genesisProtocolParamsMap) {
         itemDI = genesisProtocolParamsMap.get(new UnsignedInteger(12));
         BigDecimal decentralizationParam = itemDI != null ? toRationalNumber(itemDI) : null;
 
-        String extraEntropy = null;
+        Tuple<Integer, String> extraEntropy = null;
 //                $nonce /= [ 0 // 1, bytes .size 32 ]
         itemDI = genesisProtocolParamsMap.get(new UnsignedInteger(13)); //Removed
         if (itemDI != null) {
@@ -100,7 +100,7 @@ public ProtocolParamUpdate getProtocolParams(Map genesisProtocolParamsMap) {
             if (extraEntropyDIList.size() == 2) {
                 extraEntropy_2 = HexUtil.encodeHexString(toBytes(extraEntropyDIList.get(1)));
             }
-            extraEntropy = List.of(extraEntropy_1, extraEntropy_2).toString();
+            extraEntropy = new Tuple<>(extraEntropy_1, extraEntropy_2);
         }
 
         Integer protocolMajorVersion = null;
diff --git a/core/src/main/java/com/bloxbean/cardano/yaci/core/util/Tuple.java b/core/src/main/java/com/bloxbean/cardano/yaci/core/util/Tuple.java
new file mode 100644
index 0000000..40b43fc
--- /dev/null
+++ b/core/src/main/java/com/bloxbean/cardano/yaci/core/util/Tuple.java
@@ -0,0 +1,16 @@
+package com.bloxbean.cardano.yaci.core.util;
+
+import lombok.EqualsAndHashCode;
+import lombok.ToString;
+
+@ToString
+@EqualsAndHashCode
+public class Tuple<T, Z> {
+    public T _1;
+    public Z _2;
+
+    public Tuple(T _1, Z _2) {
+        this._1 = _1;
+        this._2 = _2;
+    }
+}
diff --git a/gradle.properties b/gradle.properties
index a166eb9..81f4f14 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,3 +1,3 @@
 group = com.bloxbean.cardano
 artifactId = yaci
-version = 0.2.3.2-SNAPSHOT
+version = 0.2.3.3-SNAPSHOT