You can bring a full gallon of marking ink in this convenient, easy-on/easy-off backpack. Stay much longer, mark much further! Trecoder® Backpack is… Lightweight – only 6 ounces when empty… only 8½ pounds when fully loaded with ink. Convenient – holds a full gallon of the brighter, longer-lasting Trecoder® inks. Complete – with 2-inch wide backstrap, 4-foot plastic tube to connect right to the Spot Gun, and the unique Spot Gun belt/holster combination.