Wildfire 18% pepper spray is hot, hot, hot. Wildfire is 18% Oleo Resin Capsicum (pepper)...a derivative of 3 Million Scoville Heat Units (SHU). Wildfire 18% pepper spray comes in 5 sizes: 1/2 ounce, 1.5 ounce, 4 ounce, 9 ounce and 1 pound. Beautiful retail packaging.