Sold as a set of two 400 lb ballast bags, the V-Drive Sacs Set works well in the rear lockers of v-drive boats or split up with one bag in the bow of the boat and one in the rear area. The Fat Sac V-Drive Sacs are sold as a set and are designed to fit in the compartments on either side of the engine in v-drive boats. The vdrive sacs are perfect for building massive wakeboarding and wakesurfing wakes. A perfect fit in the smaller lockers of v-drive boats. A pair of v-drive sacs also works great on either side of the engine in a direct drive boat for a great wakeboard wake, or put one on the side of the engine, and one between the engine and rear seat for a perfectly surfable wave.