The item weights 0.1 kg and destroys all the radiation accumulated in the body. It's five times lighter than vodka, but also much more expensive. It's unlikely to be found on the bodies of rookie stalkers.
Hints for fighting radiation
- If you need to go to an infested area for a short time (like less than 30 seconds - you don't need more time to clear a stash), just go there and ignore the radiation and dropping health. When you're done, go to a safe area and take ONE anti-rad or an adequate amount of vodka. If needed, use some food, bandages or vodka to heal your wounds, but if you have the time to wait for them to heal themselves, do it. There's no need to waste medical supplies.
- If you need to go to the area for a longer time (like the Sarcophagus), bring as much antiradiation artifacts as possible. The best is 5 Crystals or Urchins (although 3 is just fine for Sarcophagus - then the radiation won't even touch you).
- If you have little antirads or vodka, take an antiradiation artifact, get into the area, get out and watch the radiation (slowly) clear out of your body and use medical supplies or food only if your health drops low.