diff --git a/lib/database_cleaner/redis/base.rb b/lib/database_cleaner/redis/base.rb
index ec51ea2..3013240 100644
--- a/lib/database_cleaner/redis/base.rb
+++ b/lib/database_cleaner/redis/base.rb
@@ -25,7 +25,7 @@ module DatabaseCleaner
         @connection ||= begin
           if url == :default
             ::Redis.new
-          elsif db.class.is_a?(::Redis) # pass directly the connection
+          elsif db.is_a?(::Redis) # pass directly the connection
             db
           else
             ::Redis.new(:url => url)