diff --git a/app/src/main/java/com/utsmm/kbz/ui/settings/InjectKeyFragment.java b/app/src/main/java/com/utsmm/kbz/ui/settings/InjectKeyFragment.java
index 59f1227..03b3286 100644
--- a/app/src/main/java/com/utsmm/kbz/ui/settings/InjectKeyFragment.java
+++ b/app/src/main/java/com/utsmm/kbz/ui/settings/InjectKeyFragment.java
@@ -3,6 +3,7 @@ package com.utsmm.kbz.ui.settings;
 import android.os.Bundle;
 import android.text.TextUtils;
 import android.view.View;
+import android.widget.ArrayAdapter;
 import android.widget.Toast;
 
 import androidx.annotation.NonNull;
@@ -22,6 +23,9 @@ import com.utsmm.kbz.databinding.FragmentInjectKeyBinding;
 import com.utsmyanmar.paylibs.utils.LogUtil;
 import com.utsmm.kbz.util.tms.TMSUtil;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class InjectKeyFragment extends DataBindingFragment {
 
     private static final String TAG = InjectKeyFragment.class.getSimpleName();
@@ -32,6 +36,7 @@ public class InjectKeyFragment extends DataBindingFragment {
     // Key injection variables
     private DownloadFlow mDownloadFlow;
     private int keyIndexTmp = 8; // Default key index
+    private final List<HostSelectionItem> hostSelectionItems = new ArrayList<>();
 
     @Override
     protected void initViewModel() {
@@ -84,22 +89,51 @@ public class InjectKeyFragment extends DataBindingFragment {
     }
 
     private void updateConfigurationInfo() {
+            setupHostSelection();
+            binding.serialNumberValue.setText(getDisplayValue(TMSUtil.getInstance().getSerialNumber()));
+    }
 
-            String terminalId = SystemParamsOperation.getInstance().getTerminalId();
-            binding.terminalIdValue.setText(terminalId != null && !terminalId.isEmpty() ?
-                    terminalId : "Not configured");
+    private void setupHostSelection() {
+            hostSelectionItems.clear();
 
-            // Update Merchant ID
-            String merchantId = SystemParamsOperation.getInstance().getMerchantId();
-            binding.merchantIdValue.setText(merchantId != null && !merchantId.isEmpty() ?
-                    merchantId : "Not configured");
+            String primaryTerminalId = SystemParamsOperation.getInstance().getTerminalId();
+            String primaryMerchantId = SystemParamsOperation.getInstance().getMerchantId();
+            String secondaryTerminalId = SystemParamsOperation.getInstance().getThirdHostTerminalId();
+            String secondaryMerchantId = SystemParamsOperation.getInstance().getThirdHostMerchantId();
 
-            // Update Serial Number
-            String serialNo = TMSUtil.getInstance().getSerialNumber();
-            binding.serialNumberValue.setText(serialNo != null && !serialNo.isEmpty() ?
-                    serialNo : "Not configured");
+            hostSelectionItems.add(new HostSelectionItem("Primary Host", primaryTerminalId, primaryMerchantId));
 
+            if (!TextUtils.isEmpty(secondaryTerminalId) || !TextUtils.isEmpty(secondaryMerchantId)) {
+                hostSelectionItems.add(new HostSelectionItem("Secondary Host", secondaryTerminalId, secondaryMerchantId));
+            }
 
+            ArrayAdapter<HostSelectionItem> hostAdapter = new ArrayAdapter<>(
+                    requireContext(),
+                    android.R.layout.simple_list_item_1,
+                    hostSelectionItems
+            );
+            binding.actvHostSelection.setAdapter(hostAdapter);
+
+            if (!hostSelectionItems.isEmpty()) {
+                HostSelectionItem defaultSelection = hostSelectionItems.get(0);
+                binding.actvHostSelection.setText(defaultSelection.toString(), false);
+                applyHostSelection(defaultSelection);
+            }
+
+            binding.actvHostSelection.setOnItemClickListener((parent, view, position, id) -> {
+                if (position >= 0 && position < hostSelectionItems.size()) {
+                    applyHostSelection(hostSelectionItems.get(position));
+                }
+            });
+    }
+
+    private void applyHostSelection(@NonNull HostSelectionItem selectionItem) {
+            binding.terminalIdValue.setText(getDisplayValue(selectionItem.terminalId));
+            binding.merchantIdValue.setText(getDisplayValue(selectionItem.merchantId));
+    }
+
+    private String getDisplayValue(String value) {
+            return !TextUtils.isEmpty(value) ? value : "Not configured";
     }
 
     private void loadKeyFromKeyPOS() {
@@ -177,6 +211,28 @@ public class InjectKeyFragment extends DataBindingFragment {
         }
     };
 
+    private static class HostSelectionItem {
+        private final String label;
+        private final String terminalId;
+        private final String merchantId;
+
+        private HostSelectionItem(String label, String terminalId, String merchantId) {
+            this.label = label;
+            this.terminalId = terminalId;
+            this.merchantId = merchantId;
+        }
+
+        @NonNull
+        @Override
+        public String toString() {
+            return label;
+        }
+
+        private static String getSummaryValue(String value) {
+            return TextUtils.isEmpty(value) ? "Not configured" : value;
+        }
+    }
+
     // ClickEvent class for data binding - this is the proper pattern
     public class ClickEvent {
 
@@ -190,4 +246,4 @@ public class InjectKeyFragment extends DataBindingFragment {
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/app/src/main/res/layout/fragment_inject_key.xml b/app/src/main/res/layout/fragment_inject_key.xml
index 4157264..7aee3d6 100644
--- a/app/src/main/res/layout/fragment_inject_key.xml
+++ b/app/src/main/res/layout/fragment_inject_key.xml
@@ -129,6 +129,84 @@
 
                     </androidx.cardview.widget.CardView>
 
+                    <!-- Host Selection Card -->
+                    <androidx.cardview.widget.CardView
+                        android:id="@+id/hostSelectionCard"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:layout_marginBottom="16dp"
+                        app:cardBackgroundColor="@color/white"
+                        app:cardCornerRadius="16dp"
+                        app:cardElevation="2dp">
+
+                        <LinearLayout
+                            android:layout_width="match_parent"
+                            android:layout_height="wrap_content"
+                            android:orientation="vertical"
+                            android:padding="20dp">
+
+                            <TextView
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content"
+                                android:fontFamily="@font/rubik_medium"
+                                android:text="Host Selection"
+                                android:textColor="@color/colorTextTitle"
+                                android:textSize="16sp"
+                                android:textStyle="bold"
+                                tools:fontFamily="sans-serif-medium" />
+
+                            <TextView
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content"
+                                android:layout_marginTop="4dp"
+                                android:layout_marginBottom="12dp"
+                                android:fontFamily="@font/rubik_regular"
+                                android:text="Select Terminal Id and MerchantId to preview before key injection"
+                                android:textColor="@color/colorTextContent"
+                                android:textSize="14sp"
+                                tools:fontFamily="sans-serif" />
+
+                            <com.google.android.material.textfield.TextInputLayout
+                                android:layout_width="match_parent"
+                                android:layout_height="wrap_content"
+                                android:hint="Select Host"
+                                app:endIconMode="dropdown_menu"
+                                app:boxBackgroundMode="outline"
+                                app:boxCornerRadiusBottomEnd="8dp"
+                                app:boxCornerRadiusBottomStart="8dp"
+                                app:boxCornerRadiusTopEnd="8dp"
+                                app:boxCornerRadiusTopStart="8dp"
+                                app:boxStrokeColor="@color/colorPrimary">
+
+                                <com.google.android.material.textfield.MaterialAutoCompleteTextView
+                                    android:id="@+id/actvHostSelection"
+                                    android:layout_width="match_parent"
+                                    android:layout_height="wrap_content"
+                                    android:fontFamily="@font/rubik_regular"
+                                    android:inputType="none"
+                                    android:focusable="false"
+                                    android:clickable="true"
+                                    android:textColor="@color/colorTextTitle"
+                                    android:textSize="16sp"
+                                    android:paddingLeft="16sp"
+                                    tools:fontFamily="sans-serif" />
+
+                            </com.google.android.material.textfield.TextInputLayout>
+
+                            <TextView
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content"
+                                android:layout_marginTop="8dp"
+                                android:fontFamily="@font/rubik_regular"
+                                android:text="UI only: current key injection still uses the active TMS configuration."
+                                android:textColor="@color/colorTextContent"
+                                android:textSize="12sp"
+                                tools:fontFamily="sans-serif" />
+
+                        </LinearLayout>
+
+                    </androidx.cardview.widget.CardView>
+
                     <!-- Current Configuration Info Card -->
                     <androidx.cardview.widget.CardView
                         android:id="@+id/configInfoCard"