Blackheart Crucial Sight Stack Bag Black. Pre-filled with recycled rubber media for ideal weight and stability. Specifications for Blackheart Crucial Sight Stack Bag: Manufacturer: Blackheart Color: Black Features of Blackheart Crucial Sight Stack Bag: Pre-filled with recycled rubber media Velcro straps enable the stack to be fastened together Works with other Crucial stack bags Package Contents: Blackheart Crucial Sight Stack Bag Blackheart 1601245: Crucial Sight Stack Bag Black