Bling is a Tier One Perk that appears in Call of Duty: Modern Warfare 2, unlocked at level 21. It allows players to equip two attachments on their primary weapon. Bling Pro is unlocked by getting 200 kills while the Bling Perk is equipped. The Pro version of the Perk allows the player to put two attachments on their secondary weapon. Contrary to popular belief, picking up a Bling weapon and getting kills with it without having Bling equipped does not count towards completing Bling Pro challenges, despite what the description of the challenge says. However, having Bling equipped as a Perk and picking a weapon up without two attachments still counts towards the Pro challenge. However. becuase it takes up the tier one perk slot, some players may forego Bling, as they may want to choose Scavenger, especially on weapons with a small magazine or low ammo count, such as any of the sniper rifles, the AA-12, or pistols.
There are some limitations as to which attachments can go together. Players cannot combine attachments which take up the same physical space on the gun, i.e. the Grenade Launcher and the Shotgun attachment, as both are under-barrel mounted. It is also impossible to have both the Tactical Knife and Akimbo attachments on one gun, as both require the player's left hand. Additionally, players cannot combine Akimbo with any kind of sights as it would be pointless. The Rapid Fire, Suppressor, Heartbeat Sensor, Extended Magazines, and FMJ attachments do not conflict with any other attachments.
- When prompted to pick up a weapon, the pickup text will only denote that the weapon has two attachments by adding the word "Bling" after the name of the weapon. The only attachment that is visible is Akimbo, since it changes the pickup icon.
- In early production, Bling was supposed to allow two attachments for both primary and secondary and the Pro version was to allow three attachments where available.
- In Call of Duty: Modern Warfare 2's campaign, Akimbo weapons with sights can be found, an impossible Bling setup in multiplayer.
- When using the Shotgun attachment on an assault rifle paired with the Silencer or FMJ, the Shotgun will also acquire the Silencer or FMJ effect.
- In Call of Duty: Modern Warfare 3, the name for getting a certain amount of kills with a weapon that has the Attachments Proficiency is "Bling Bling", an obvious reference to the Perk in Call of Duty: Modern Warfare 2.