This Costar Clear 384-Well Microplate / Pack of 18 came from a local lab that had surplus inventory. The bag was opened and two plates were removed. The remaining 18 plates are all in new, unused condition. We urge customers to view all photos as they show overall condition, included accessories and useful information. Unfortunately, there are no markings indicating part number. We will be happy to provide additional information as well as pictures so please feel free to contact us with any questions.