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Modern Warfare 2 Combat Controllers (Xbox 360 and PS3)
A specialized controller for Modern Warfare 2, the Combat Controller will incorporate rubber grips and a soft-touch finish for prolonged frag sessions. Additionally
the controller will include two buttons toward the rear of the controller, which allows players to remap action buttons or thumbstick commands on the fly, allowing users to relocate melee or sprint commands to rear buttons for added control. As an aesthetic touch, the Combat Stick will feature thumbstick backlighting and a durable braided USB cable for extra visual panache. Aside from the clear visual variations, the PS3 controller will depart from the Xbox 360 design in that it utilizes a 2.4GHz wireless system with internal rechargeable battery for up to 60 hours of gameplay.
Both variations of the Modern Warfare 2 Combat Controller will retail for $49.99.
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video:
in other words; you can simulate RS click with the new button thus freelook in cockpit will be more easy (I think, have not tried this of course)