Hi-Gear SYNTHETIC ENGINE CLEANER FOR OIL UPGRADE (with SMT2). It is used for engines of all types when you switch from mineral oil to semi-synthetic or synthetic one and from semi-synthetic oil to synthetic one. It has a complex effect on the lubricated surface and on the motor oil. It comprises the synthetic metal conditioner of the second generation SMT2 which protects rubbing engine parts from negative impacts of removed contaminants.