A regular key designated with the letter "A".
― In-game description
Key A is a mission item in S.T.A.L.K.E.R.: Call of Pripyat.
Description[]
It is one of two keys that must be acquired during the mission Bloodsucker Lair (the other being Key B) in order to open the container containing the Perin B3 gas. This key is found on the Preobrazhensky Bridge in Zaton, inside a locker found on the rear of a UAZ-469 vehicle found on the bridge. Inside the locker is also a copy of Internal order No. 423 and Order No. 562.