Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number AK500 found under Filter Media Air Conditioning by United Refrigeration Inc. The National Stock Number assigned to this part is 4130013202625, and the Federal Supply Class is 4130 Refrigeration And Air Conditioning Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like AK500.