10th lobby
Reach level 70 and it magically appears in your list of weapons.
You unlock it at level 42 and I suggest getting akimbo with it.
Go up levels
if u mean what level u have to be to prestige in mw2 the answer is level 70
use the attachment akimbo
You cant.
The highest level you can achieve is Level 70. Prestige 10. Prestige by getting to lvl 70 then go to barracks and click prestige mode
to unlock the stinger missle in mw2 you must be level 30 or sergent major II
Reach Prestige 1 and Level 69.
Level 4
Sleight of Hand Pro
Level 70, which is the level cap.