Find the perfected suit is an optional side mission featured in Shadow of Chernobyl.
Acquiring the mission
Completing the quest
The mail jacket is located within a tunnel that connects the Cordon to the Dark Valley. A Pseudodog lives inside the tunnel, so a shotgun is suggested for the mission. However, a single pistol head shot is almost as easy from the safe height of the container or concrete. The reward for the mission is a Stone Flower artifact.
Behind the Scenes
The player's character was to be originally rewarded with 4000 RU in addition to the artifact. This feature was commented out in the script file. 
- Shadow of Chernobyl 1.0006; task_manager.ltx; line 1897