Double Tap is a perk featured in every map, except Anstieg. It costs 2000 points to buy, and increases the firing speed of the players weapons by about 1/3 times faster, (If single shot such as the ballistic knife or panzershrek, no effect.)

Pro's- good for repeater arms, such as the k98k or trench gun, and good for slow auto weapons on later rounds.

Con's- Increases speed of all weapons except single shot, so is very bad on low ammo or small magazine weapons.  

Double Tap

Double Tap perk-a-cola machine

Double Tap bottle

A player drinking double tap perk-a-cola