Ordered a case of 10 vials (10ml) GP Phenyl 100 (GP NPP 100) on 11/06/2022. Waited to run two full cycles before posting a review based on experience and results. Initial concern once received was none of the 10 vials had an ISN#. I generated a workticket (#VLU-770-61824) with Napsgear on 11/23/2022 and after sending the issue up to a higher level, received a response on 12/07/2022 that the fulfillment center confirmed it was a printing error at the factory and that the product was "absolutely authentic." After running two modest cycles -- 12 weeks on and 7 weeks off, the GP NPP 100 has worked very well. Cycle was .8ml on Mon, Wed and Fri with .4ml of GP Test Cyp 250 combined in the same syringe. Joints and attachments felt better mid and end cycle. Very pleased with the product and service provided by Napsgear.