Starter Boat Ballast KitFatsac Rear Locker Fat Sac Pair Sold as a set of two 400lb ballast bags, the Fatsac Rear Locker Fat Sacs work well in the rear lockers of v drive boats, or split up with one in the bow and one in the rear. They are the same height and width as the Centre 750lb sac but shorter in length, making them a perfect fit in the smaller lockers of v drive boats. A pair also works great on either side of the engine in a direct drive boat for a great wakeboard