This is a set of two replacement gaskets for Muji's airtight jars. They are new and unopened. I believe the airtight jars themselves are now discontinued. The last photo shows the product numbers of the applicable airtight jars, so please check them. These are the same parts for the 500mL, 750mL, and 1,000mL sizes. I had these in stock, but I no longer need them, so I'm offering them to someone who does. ⚠️ Although unopened, they seem slightly yellowed. I'm not sure because I have nothing to compare them to, but please understand that they have been stored at home for a long time. I don't think there is any deterioration such as cracks in the rubber. If you would like to purchase them with other items I have listed, I may be able to offer a discount on combined shipping, so please feel free to ask (^-^) (Please let me know in the comments before you buy.) Thank you very much (*^*)