diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 7195d63..2e621be 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -2704,6 +2704,7 @@
 
 #if defined(MBEDTLS_SSL_RECORD_SIZE_LIMIT)
 #define MBEDTLS_SSL_RECORD_SIZE_LIMIT_EXTENSION_DATA_LENGTH (2)
+/* This value is defined by RFC 8449 */
 #define MBEDTLS_SSL_RECORD_SIZE_LIMIT_MIN (64)
 
 MBEDTLS_CHECK_RETURN_CRITICAL