It is not unusual for the state Military Police operating armored vehicles in the “flavelas” of Rio de Janeiro in Brazil to encounter gunfire from drug traffickers as they patrol this hilly terrain. 
This time however, shots from an AR-15 semi-automatic rifle did not cause flat tires and the Military Police were able to complete their mission without fear of abandoning their vehicle due to flat tires.
Compared to solid rubber tires, the softer durometer foam fill used, SuperFlex, was able to provide a flatproof option reaching speeds up to 55mph with the proper deflection and ride comfort to both the vehicle and operator. 
Commonly referred to as foam fill, tire fill, and poly fill, Arnco’s patented products reduce downtime related to punctured tires or flat tires. The liquid polyurethane is pumped into the tire through the valve stem until it replaces all of the air which now results into a solid tire, but with a softer ride than a solid rubber tire. The result are flatproof tires that improve the productivity of the equipment.