When this grenade explodes, it creates 30 fragments which rapidly fly in all directions. If the grenade falls on the middle of a tank some of the fragments instantly deal damage, but others fly away. it deals maximum damage if the tank is located on the bottom of the map.
The shrapnel don't deal enough damage? Upgrade it to shredders! It creates 40 fragments instead of 30, but the damage is the same. The thing is, it deals up to 250 damage if all the fragments impact...
This weapon is more effective at the ground of the map. This is likely due to the projectiles spawning and immediately hitting the indestructible ground layer. To land precisely on flat land, shoot at the three-quarters mark of you and your destination.