If the canister contains a tactical round, the top forward left corner and top rear right corner will be marked with three 4-inch yellow squares. If the canister is empty or ballasted for training, the top forward left corner and top rear right corner will be marked with three 4-inch gold squares. Canisters with gold squares will also be marked ′′EMPTY′′ indicating canister does not contain a missile and/or ballast, or ′′DUMMY′′ indicating canister is weighted with ballast for training. If the canister is a Missile Round Trainer (MRT) the top forward left corner and the top rear right corner will be marked with three 4-inch light blue squares. Canisters with light blue squares will also be marked ′′Missile Round Trainer′′ indicating canister emulates a ready-round missile in size, shape, weight, and electrical connections. Refer to TM 9-1425-1601-12 for missile canister markings.