All the units in the ONE POINT FOUR line start with Fox Labs' famous legacy formula using 5.3 million Scoville Heat Units (SHU) OC pepper - then they DOUBLE the pepper content which doubles the MC (Major Capsaicinoids) to almost blistering levels. 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. Now the ONE POINT FOUR has increased the heat, and this is becoming the most demanded product from Law Enforcement agencies nationwide. It's an oil based pepper spray (most pepper sprays are water) giving the spray greater distance and stronger effects on impact. The ONE POINT FOUR PEPPER SPRAY also includes invisible UV marking dye for suspect identification.