Krink sprayer! Pumped up by hand, with plastic body that holds 5 liters, hose, steel handle with button and brass nozzle.
Fill with your choice of color, keeping in mind that the consistency should be thin.
"The Sprayer is a hand-pressurized paint delivery system. It will take a bit of trial and error, but once you master the process you can achieve unique marks on a large scale." - KRINK