diff --git a/lib/src/bitcoin/script/op_code/constant.dart b/lib/src/bitcoin/script/op_code/constant.dart
index 59ac86e..0725415 100644
--- a/lib/src/bitcoin/script/op_code/constant.dart
+++ b/lib/src/bitcoin/script/op_code/constant.dart
@@ -150,7 +150,7 @@ class BitcoinOpCodeConst {
   static const List<int> emptyTxSequence = [0x00, 0x00, 0x00, 0x00];
 
   static const List<int> absoluteTimelockSequence = [0xfe, 0xff, 0xff, 0xff];
-  static const List<int> replaceByFeeSequence = [0x01, 0x00, 0x00, 0x00];
+  static const List<int> replaceByFeeSequence = [0xfd, 0xff, 0xff, 0xff];
 
   /// Script version and Bitcoin-related identifiers
   static const int leafVersionTapscript = 0xc0;
diff --git a/lib/src/transaction_builder/forked_transaction_builder.dart b/lib/src/transaction_builder/forked_transaction_builder.dart
index a3c2973..e999905 100644
--- a/lib/src/transaction_builder/forked_transaction_builder.dart
+++ b/lib/src/transaction_builder/forked_transaction_builder.dart
@@ -259,9 +259,11 @@ that demonstrate the right to spend the bitcoins associated with the correspondi
         );
     }
     final inputs = sortedUtxos.map((e) => e.utxo.toInput()).toList();
-    if (enableRBF && inputs.isNotEmpty) {
-      inputs[0] =
-          inputs[0].copyWith(sequence: BitcoinOpCodeConst.replaceByFeeSequence);
+    if (enableRBF) {
+      for (int i = 0; i < inputs.length; i++) {
+        inputs[i] =
+            inputs[i].copyWith(sequence: BitcoinOpCodeConst.replaceByFeeSequence);
+      }
     }
     return Tuple(List<TxInput>.unmodifiable(inputs),
         List<UtxoWithAddress>.unmodifiable(sortedUtxos));
diff --git a/lib/src/transaction_builder/transaction_builder.dart b/lib/src/transaction_builder/transaction_builder.dart
index 36ffeac..0e29921 100644
--- a/lib/src/transaction_builder/transaction_builder.dart
+++ b/lib/src/transaction_builder/transaction_builder.dart
@@ -400,9 +400,11 @@ that demonstrate the right to spend the bitcoins associated with the correspondi
         );
     }
     final inputs = sortedUtxos.map((e) => e.utxo.toInput()).toList();
-    if (enableRBF && inputs.isNotEmpty) {
-      inputs[0] =
-          inputs[0].copyWith(sequence: BitcoinOpCodeConst.replaceByFeeSequence);
+    if (enableRBF) {
+      for (int i = 0; i < inputs.length; i++) {
+        inputs[i] =
+            inputs[i].copyWith(sequence: BitcoinOpCodeConst.replaceByFeeSequence);
+      }
     }
     return Tuple(List<TxInput>.unmodifiable(inputs),
         List<UtxoWithAddress>.unmodifiable(sortedUtxos));