(Top) A portion of the Aft Integrated Electronics Assembly (IEA). The "Milk Can" cover (left) on the Booster's Upper Strut. Just behind it (and harder to see) is the Diagonal Strut. On the other side of the Booster (not seen) is the Lower Strut. These struts do not carry any thrust load during launch - only lateral loads to keep the Boosters from pulling away from the External Tank (ET).