Schematic: Extreme-Impact Hole Puncher

Schematic: Extreme-Impact Hole Puncher is a recipe used in Engineering (a schematic). It is used to learn how to create a Extreme-Impact Hole Puncher, a type of gun.

Source
This schematic is sold by at the Molten Front (Firelands) which can be accessed through a portal in Mount Hyjal. To be able to see Bloombeard you'll have to complete the quests Quest:Druids of the Talon and Quest:The Shadow Wardens which each require 125x Mark of the World Tree, and furthermore Quest:Additional Armaments - which also require 125 marks - to unlock Bloombeard's wares. The schematic itself is sold for.