Modern warfare 2 perks

Perk Slot 1

Marathon | Marathon Pro

Ability: Unlimited sprint.

Pro Ability: Get over obstacles faster.

Sleight of Hand | Sleight of Hand Pro

Ability: Faster reloading.

Pro Ability: Gives a speed boost to how fast you can aim down the sight of your weapon.

Scavenger | Scavenger Pro

Ability: Full resupply from dead enemies.

Pro Ability: Extra magazines.

Bling | Bling Pro

Ability: 2 primary weapon attachments.

Pro Ability: 2 secondary weapon attachments.

One Man Army | One Man Army Pro

Ability: Replaces your secondary weapon. This allows you to change your class at any given time during a match.

Pro Ability: Swaps classes even faster.

Perk Slot 2

Stopping Power | Stopping Power Pro

Ability: Increased bullet damage.

Pro Ability: Increased bullet damage vs. helicopters and aircrafts.

Lightweight | Lightweight Pro

Ability: Move faster.

Pro Ability: Allows you to do a quick aim after sprinting.

Hardline | Hardline Pro

Ability: Killstreaks require 1 less kill.

Pro Ability: Death Streaks require 1 less death.

Cold-Blooded | Cold-Blooded Pro

Ability: Undetectable by UAV, air support, Sentry Guns, and thermal.

Pro Ability: No red crosshair or name shown when you are targeted.

Danger Close | Danger Close Pro

Ability: Increases explosive weapons damage.

Pro Ability: Increases air support damage.

Perk Slot 3

Commando | Commando Pro

Ability: Increased melee distance.

Pro Ability: You don't take any damage from falling.

Steady Aim | Steady Aim Pro

Ability: Increased hip-fire accuracy.

Pro Ability: You can hold your breath for a longer period of time.

Scrambler | Scrambler Pro

Ability: Scrambles (jams) the enemy radar in a small radius.

Pro Ability: Delays enemy Claymores, thus allowing you to avoid the explosion if you are fast enough.

Ninja | Ninja Pro

Ability: Invisible to heartbeat sensors.

Pro Ability: Allows you to move silently.

SitRep | SitRep Pro

Ability: Insertions. This will reveal enemy explosives and Tactical Insertions.

Pro Ability: Makes enemy footsteps louder.

Last Stand | Last Stand Pro

Ability: Allows you to survive a normal death. You will drop to the ground and pull out your pistol.

Last Stand ends after ~10 seconds or if you get shot again, which results in your death. You can also crawl in the Last Stand mode.

Pro Ability: You get to use your equipment too, like frag grenades and throwing knives.