diff --git a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch
index 271ce66..9a255be 100644
--- a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch
+++ b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch
@@ -53,7 +53,7 @@
       <!-- node params -->
 
       <param name="is_multiple" value="$(arg is_multiple)" />
-      <param name="serial_number" value="$(arg serial_number)" />
+      <param name="serial_number" type="string" value="$(arg serial_number)" />
 
       <param name="depth_type" value="$(arg depth_type)" />
 
diff --git a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_1.launch b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_1.launch
index 06046e4..4071d2b 100644
--- a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_1.launch
+++ b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_1.launch
@@ -53,7 +53,7 @@
       <!-- node params -->
 
       <param name="is_multiple" value="$(arg is_multiple)" />
-      <param name="serial_number" value="$(arg serial_number)" />
+      <param name="serial_number" type="string" value="$(arg serial_number)" />
 
       <param name="depth_type" value="$(arg depth_type)" />
 
diff --git a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_2.launch b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_2.launch
index 206dcf3..8824669 100644
--- a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_2.launch
+++ b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/sub/mynteye_2.launch
@@ -53,7 +53,7 @@
       <!-- node params -->
 
       <param name="is_multiple" value="$(arg is_multiple)" />
-      <param name="serial_number" value="$(arg serial_number)" />
+      <param name="serial_number" type="string" value="$(arg serial_number)" />
 
       <param name="depth_type" value="$(arg depth_type)" />