Picture of the Grenade in Real Life
It was the standard hand grenade used by the German Nazis during World War Two. It was reffered to as "The Potato Masher" or "The Stick" by the British Soldiers because of its shape.
 Call of Duty
In Call of Duty 3 you can carry up to 5 of these at a time, they are important in the game especially when you are going through houses in Chambois. There is not really any difference between this grenade and the grenade carried by the Allied forces.