You have to check what kind of pen you are buying. If it is the most common press-type inerasable pen with ordinary packaging, you may have been cheated. I saw this code. 49025054 represents erasable, and 1 represents a refill. I don’t know from now on. This is not an old model, it should be a new one. There are many members of the FRIXION series, just like the two I used, they have been used for half a year. I haven't changed the pen cases. One is a metal pen case that I bought for 178, and the other is a three-color pen that I bought on sale for 39. They are both good. Plastic pen cases are easy to break. Baile's ones are too precise. They cost 45 yuan. The F-tip Baile fountain pen I bought broke when I touched it. Ahem, let’s get back to the topic. This is a genuine product! However, I advise you to use less erasable pens and spend a thousand or eight hundred dollars to buy a better gold pen. Parker and Hero are all classics. My Picasso is also good. It is forbidden to use erasable pens during the exam. I wish you progress in your studies and make progress every day!