COMBAT OUTPOST SHIR GHAZAY, Helmand province, Afghanistan -- Reynoldsburg, Ohio native Lance Cpl. Zachary Parker pumps grease into a track wheel. The 21-year-old tank mechanic with Alpha Company, 2nd Tank Battalion, 2nd Marine Division (Forward), also doubles as a driver for the M88A2 Hercules recovery vehicle. Parker, a 2008 graduate of Reynoldsburg High School, must help keep the recovery vehicle and 14 M1A1 Abrams Main Battle Tanks functioning.