diff --git a/doc/src/faq.rst b/doc/src/faq.rst
index 4fae77af..e754a427 100644
--- a/doc/src/faq.rst
+++ b/doc/src/faq.rst
@@ -80,13 +80,12 @@ My database is Unicode, but I receive all the strings as UTF-8 `str`. Can I rece
     See :ref:`unicode-handling` for the gory details.
 
 Psycopg converts :sql:`decimal`\/\ :sql:`numeric` database types into Python `!Decimal` objects. Can I have `!float` instead?
-    You can register the `~psycopg2.extensions.FLOAT` typecaster to be used in
-    place of `~psycopg2.extensions.DECIMAL`::
+    You can register a customized adapter for PostgreSQL decimal type::
 
         DEC2FLOAT = psycopg2.extensions.new_type(
             psycopg2.extensions.DECIMAL.values,
             'DEC2FLOAT',
-            psycopg2.extensions.FLOAT)
+            lambda value, curs: float(value) if value is not None else None)
         psycopg2.extensions.register_type(DEC2FLOAT)
 
     See :ref:`type-casting-from-sql-to-python` to read the relevant