High Quality Content by WIKIPEDIA articles! The 20th Infantry Regiment ("Sykes` Regulars") is a United States Army infantry regiment. Currently only the 5th Battalion of the 20th Infantry still exists. Stationed at Fort Lewis, WA and part of the 3rd Stryker Brigade Combat Team, 2nd Infantry Division, 5-20 Infantry was one of the original battalions selected to take part in the testing and fielding of the Army`s new Stryker vehicle.