Select the Codenames option, then enter the codes at the Secrets Screen. Save your Codename after entering the code.
All gadget upgrades - Enter Q LAB on the passcode screen.
Larger clip, sniper rifle - Enter MAGAZINE on the passcode screen.
Rifle scope upgrade - Enter SCOPE on the passcode screen.
Camera upgrade - Enter SHUTTER on the passcode screen.
Decrypter upgrade - Enter SESAME on the passcode screen.
P2K upgrade - Enter P2000 on the passcode screen.
Golden P2K - Enter AU P2K on the passcode screen.
Golden PP7 - Enter AU PP7 on the passcode screen.
Grapple upgrade - Enter LIFTOFF on the passcode screen.
Laser upgrade - Enter PHOTON on the passcode screen.
Stunner upgrade - Enter ZAP on the passcode screen.
Tranq dart upgrade - Enter SLEEPY on the passcode screen.
Car missile upgrade - Enter LAUNCH on the passcode screen.