diff --git a/README.md b/README.md
index dccdec2..08790ab 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,8 @@ itself a port of [Google's libphonenumber](https://github.com/googlei18n/libphon
 It provides an equivalent functionality, with the following implementation differences:
 
 - `PhoneNumber` is an immutable class; it can be safely passed around without having to worry about the risk for it to be changed;
-- `PhoneNumber` is not just a mere data container, but provides all the methods to parse, format and validate phone numbers; it transparently encapsulates `PhoneNumberUtil`.
+- `PhoneNumber` is not just a mere data container, but provides all the methods to parse, format and validate phone numbers; it transparently encapsulates `PhoneNumberUtil`;
+- `PhoneNumberFormat` and `PhoneNumberType` are native PHP enums.
 
 ## Installation