The knife spear clean is a two-handed melee weapon. It is similar in appearance to the regular knife spear, but it does 25% more damage, has a higher critical hit chance and causes bonus limb damage. Its special V.A.T.S. attack is The Mauler (requires a Melee Skill of 50 or more) which costs 35 action points and can knock an opponent down or disarm them.
The knife spear clean can be crafted in any workbench found around the Villa or districts around the Dead Money map. The weapon can also be crafted outside of the dead money add-on if the correct items are present.
The workbench recipe is listed as "cosmic knife spear", but the weapon will appear in the player's inventory as "knife spear clean".
PCPlayStation 3Xbox 360 This weapon appears mostly identical to the standard knife spear, notably the knives themselves, which do not appear to be clean. This is caused by the special, "clean" texture for the weapon only being applied to the staff portion of the weapon and not the blade portion.
PCPlayStation 3Xbox 360 The knife spear clean is marked as a "Player Only" weapon, meaning it cannot be given to companions for use.
At some point in the add-on, the spear will not be able to knock down any ghost people, it is only after the final quest that ghost people are able to be knocked back down.