Derek "Frost" Westbrook

 is a Staff Sergeant in Delta Force. He is one of the confirmed playable characters for Call of Duty: Modern Warfare 3.

Trivia

 * Based on the E3 demo for Call of Duty: Modern Warfare 3, the way in which Frost places his hand on the vertical forward grips of his weapons is the same taught in Magpul Dynamics tactical Carbine courses. In which the shooter places the the thumb of his vertical grip hand on the side of the weapon, while resting the rest of his hand and fingers on the vertical grip. The reason for this is to get a better control of the rifle when turning it towards the target and stopping it from swaying quicker.