Inside surface is very rough. There are machine oil that stuck in the abundant pitting hole inside the pot. Please refer to attached photos taken by microscope. Have tried to clean numerous times but still cannot clean all. Strongly advise to buy stainless steel cooker because the inside surface will be smooth and easier to clean. Another issue is kitchen mittens are needed to open the cooker after use because you need to hold the hot part to open the pot.
I do not know about the product because I haven't seen it yet as I have to go to collect it and pay around 50٪ more in duty . that is mentioned by the seller in small print . when it was mentioned to the seller they sent me a copy of there small print with a sarcastic smiley imoji . If you are in UK do not buy from these people items are more expensive than the high Street and not as good quality with no regulation. Do make the mistake of thinking Chinese mean nice and cheap. It is neither nice or cheap. plus rudeness as a bonus.