diff --git a/media/mtp/MtpStringBuffer.h b/media/mtp/MtpStringBuffer.h
index cbc8307..e5150df 100644
--- a/media/mtp/MtpStringBuffer.h
+++ b/media/mtp/MtpStringBuffer.h
@@ -19,6 +19,9 @@
 
 #include <stdint.h>
 
+// Max Character number of a MTP String
+#define MTP_STRING_MAX_CHARACTER_NUMBER             255
+
 namespace android {
 
 class MtpDataPacket;
@@ -29,7 +32,7 @@
 private:
     // mBuffer contains string in UTF8 format
     // maximum 3 bytes/character, with 1 extra for zero termination
-    uint8_t         mBuffer[255 * 3 + 1];
+    uint8_t         mBuffer[MTP_STRING_MAX_CHARACTER_NUMBER * 3 + 1];
     int             mCharCount;
     int             mByteCount;