All 6.6 Liter DPF Delete tuning products are STRICTLY FOR OFF-ROAD USE ONLY. According to the EPA Clean Air Act, they are illegal for use on any Federal, State, or Local public highways and illegal use is punishable by the penalties enacted by the mentioned laws. We do not condone illegal use of these products, and an Environmental and Liability waiver must be signed in order to purchse any DPF Delete products.