Advanced radiation suit (Fallout 3)

The Advanced Radiation Suit is a suit specially designed to stop radiation better than the standard Radiation Suit. It covers the entire body. As such, it is impossible to wear a helmet or glasses with this armor, except the Biker Goggles.

Locations
It can be found deep within Vault 87, in the Test Labs. When you get to the room with the Lab Technician's terminal (on a desk to the right) one of the options will be to unlock the storage room. Choose that option, then turn around and go back out the door you entered and turn left. That door is the storage room and contains the Advanced Radiation Suit.

Another can be found in the Franklin Metro Utility, in a box titled "Radiation Suit Case", at the bottom of a flooded tunnel.

One can also be found in the Point Lookout add-on during a quest.

Can also be bought from Moira at Craterside Supply, Gustavo from Tenpenny Tower, Karl at Meresti Metro Station, Tulip in the Underworld, Flak 'N Shrapnel's in Rivet City, Crow if you invest the maximum amount into his inventory and Knight Captain Durga in the Citadel if you get permission to trade.

Their is also one during the final scene of prodject purity on the body of a dead enclave scientist

Some can be taken from enclave scientists by means of a random encounter in the wastes

Appearances
The appears only in Fallout 3.