diff --git a/components/UVCStream/UVCStream/UVCStream.cpp b/components/UVCStream/UVCStream/UVCStream.cpp
index 1c381b9..2c61d27 100644
--- a/components/UVCStream/UVCStream/UVCStream.cpp
+++ b/components/UVCStream/UVCStream/UVCStream.cpp
@@ -3,9 +3,8 @@ constexpr int UVC_MAX_FRAMESIZE_SIZE(75 * 1024);
 
 static const char *UVC_STREAM_TAG = "[UVC DEVICE]";
 
-extern "C"
-{
-  static char serial_number_str[13];
+extern "C" {
+  static char serial_number_str[18];
 
   const char *get_uvc_device_name()
   {
@@ -24,8 +23,9 @@ extern "C"
         return CONFIG_TUSB_SERIAL_NUM;
       }
 
-      sniprintf(serial_number_str, sizeof(serial_number_str), "%02x:%02x:%02x:%02x:%02x:%02x",
-                mac_address[0], mac_address[1], mac_address[2], mac_address[3], mac_address[4], mac_address[5]);
+      sniprintf(serial_number_str, sizeof(serial_number_str), "%02X:%02X:%02X:%02X:%02X:%02X",
+          mac_address[0], mac_address[1], mac_address[2], mac_address[3], mac_address[4], mac_address[5]
+      );
     }
     return serial_number_str;
   }