on the fifth floor in the thick hallway
To get the card key in Pokémon Fire Red you need to go the 5th floor in the Silph Company. You will find the card key after defeating the Team Rocket members.
go to5F and to the "bottom" of the floor and there i is, then go to 3F and unlock some doors and warp to your rival
The card key is located on the 5th floor of the Silph Co. building in Saffron City.
baby fat
the one in the right, you need to have the card key
you find it in the Pokemon mansion
You find the red key card when you chase the thief on the scooter. You don't use it right away. The key card opens the door to the Black Widow's art room, where you complete the game. (You need the key from the curator of the Museum to track her down.)
You can find the key to unlock the door in Pokemon mansion
Go to F5. Go all the way down. You will see a member of Team Rocket standing beside a teleporter. Step on the teleporter. Once you have teleported to different room (with a scientist in it) step on the SAME teleporter that you came from to return. Go right and you will find the card key.
you open a lift with it
The red card dropped by the Black Widow is a key card that opens the vault in her underground lair. If you return to the museum after picking up the card, you will receive a package that takes you to another island, to enable you to find the missing painting.
You have to go into Pokemon mansion. Find the key in the basement.