The Chainsword is the common assault weapon of the Space Marine chapters.
It looks like a sword with a chain instead of the cutting edge.
The chain got choppers that are of monomolekular size.
These allow to cut through armour and flesh easily.

The Frag Grenade is the standard grenade in the 40k universe.
If it explodes it catapults dozens of razorsharp shrapnels which cut through armour and flesh. 
  
The Bolt Pistol is the little brother of the Bolter.
It has a decreased range, less rate of fire but the same penetration power. 
  
