What you can not get clean with Attila extra-strong, you can throw it away safely. We use this cleaner for barbecue (ie the plates and grids) and the oven if it is very dirty. As a rule, a cleaning cycle lasts - ie evenly spray, wait (~ 1 hour), clean scrub and then rinse thoroughly. For long exposure (eg overnight) does not help the cleaner dries sometime a. Only when not everything gets clean, a second cleaning cycle is required, very rarely, a third (if Grandma has her oven not been cleaned for three years, but baked regular and fried). In parts of the grill you should work with a brass wire brush, when coated material (oven) with a pot sponge, so that the coating is not damaged. Note Anyway: The cleaner is quite aggressive, possibly wearing dish-washing gloves, making sure that nothing splashes into the eyes, if something comes to your skin, wash off quickly and thoroughly. If one considers that, nothing can go wrong. I have so many part so get clean, which I would otherwise probably thrown away.
