FATSAC Rear Seat/Center Locker Ballast Bag - 650lbs - Gray [W705-GRAY]Rear Seat Center Locker Ballast Bag 650lbs Gray The FatSac Seat Center Locker Sac is a versatile ballast bag that works well in place of the rear seat on inboards, in the center locker, or anywhere else it fits. The FatSac Center Locker Rear Seat Sac is one of the most versatile wakeboard ballast bags that FatSac currently offers, finding a perfect home in many locations throughout the boat. Its low profile design means it will fit in many storage