diff --git a/Class/CDC/Inc/usbd_cdc_if.h b/Class/CDC/Inc/usbd_cdc_if.h
index 080e913..f5336ee 100644
--- a/Class/CDC/Inc/usbd_cdc_if.h
+++ b/Class/CDC/Inc/usbd_cdc_if.h
@@ -29,8 +29,8 @@ extern "C" {
 
 /* Exported types ------------------------------------------------------------*/
 /* Exported constants --------------------------------------------------------*/
-#define APP_RX_DATA_SIZE  512
-#define APP_TX_DATA_SIZE  512
+#define APP_RX_DATA_SIZE  64
+#define APP_TX_DATA_SIZE  64
 
 extern USBD_CDC_ItfTypeDef  USBD_CDC_Template_fops;