The MATRIOSAC is a set of two round, foldable bags for storing throwlines and throwbags. The bags are designed to fit inside of each other and fold to a compact size. Two sets of throwing gear can be stored. The larger blue bag also features a large pocket under the bag for storing extra gear. Folding the bags holds the throwline flat at the bottom, creating an easy way to store and carry throwline without creating twists or knots. The bags are kept flat with two sets of Velcro straps. Once the MATRIOSAC is opened, it is held on the ground by the weight of the throw weights and other accessories stored in the bag. The bottom is reinforced and waterproof. The result of this bag is a compact storage bag that is stronger, less prone to being blown over, and offers better protection against ground moisture.