In the Zone, the RDG-5 is the most common explosive device available and carried by most stalkers, it is also fairly cheap with one costing about 500-600 rubles per piece only. Although it has a low blast radius, the RGD is invaluable for room clearing and urban combat as due to its low powered nature, its explosion limits its destruction to a small area.
The RGD-5 is only slightly weaker than the F1 grenade - at point-blank range it can only deal 300 damage as opposed to the Efka's 360. The main difference is that the RGD-5 has a smaller blast radius than the F1.
Shadow of Chernobyl
An offensive hand grenade with a small radius of splinter damage.
Shadow of Chernobyl in-game description
The grenades can be obtained from the following stashes: