All the units in the Five Point Three line contain their famous 2% formula using 5.3 million Scoville Heat Units (SHU) OC pepper. This is one of the only true Police Strength pepper sprays on the market, and the original legacy formula that is carried by police, correctional officers and the United States military. It's an oil based pepper spray (most pepper sprays are water) giving the spray greater distance and stronger effects on impact. This is one of the most carried formulas by law enforcement officers worldwide, and their best selling original formula. The 5.3 also includes invisible UV marking dye for suspect identification.