Both of these are in-house Harbor Freight names ... but you can usually track down YouTube reviews of people testing out the air compressors. For example, the McGraw 3 Gallon, 1/3 HP, 110 PSI ...
These are the reed valves as found in fits for Central Pneumatic Harbor Freight air compressors as well as Sears Craftsman E100229 and others. You will receive (2) reed valves with your purchase.