diff --git a/core-buffer/include/BufferUtils.hpp b/core-buffer/include/BufferUtils.hpp
index d1e07eb..10f022d 100644
--- a/core-buffer/include/BufferUtils.hpp
+++ b/core-buffer/include/BufferUtils.hpp
@@ -7,6 +7,7 @@ namespace BufferUtils
 {
     extern const size_t FILE_MOD;
     extern const size_t FOLDER_MOD;
+    extern const std::string FILE_EXTENSION;
 
     std::string get_filename(
             std::string root_folder,
diff --git a/core-buffer/src/BufferUtils.cpp b/core-buffer/src/BufferUtils.cpp
index a37491f..5647e32 100644
--- a/core-buffer/src/BufferUtils.cpp
+++ b/core-buffer/src/BufferUtils.cpp
@@ -7,6 +7,7 @@ using namespace std;
 const size_t BufferUtils::FILE_MOD = 1000;
 // Must be power of 10 and >= than FILE_MOD.
 const size_t BufferUtils::FOLDER_MOD = 100000;
+const std::string BufferUtils::FILE_EXTENSION = ".h5";
 
 string BufferUtils::get_filename(
         std::string root_folder,
@@ -23,7 +24,7 @@ string BufferUtils::get_filename(
     folder << root_folder << "/";
     folder << device_name << "/";
     folder << folder_base << "/";
-    folder << file_base << ".bin";
+    folder << file_base << FILE_EXTENSION;
 
     return folder.str();
 }
diff --git a/core-buffer/test/test_buffer_utils.cpp b/core-buffer/test/test_buffer_utils.cpp
index 95a785e..53182a4 100644
--- a/core-buffer/test/test_buffer_utils.cpp
+++ b/core-buffer/test/test_buffer_utils.cpp
@@ -5,7 +5,8 @@ using namespace std;
 
 TEST(BufferUtils, get_filename)
 {
-    auto expected_file = "/root/device-1/12300000/12345000.bin";
+    auto expected_file = "/root/device-1/12300000/12345000" +
+            BufferUtils::FILE_EXTENSION;
 
     auto root_folder = "/root";
     auto device_name = "device-1";