I purchased this last year! It's a sterilizer that fits one baby bottle. Please note that I have disposed of the instruction manual and the outer box. I think it's convenient for taking with you or keeping at your parents' house ☺︎ How to use it: ① Fill the yellow container with water up to the water line. ② Place the rack. ③ Place nipples and holders on the bottom, and the bottle on top, then close the lid completely. ④ Heat for 3 minutes at 600W or less. ⑤ Take it out of the microwave after it has cooled. Feel free to ask any questions in the comments ☺︎