GENUINE SPARE PARTS are manufactured by the main manufacturer. The parts are branded with a stamp or a logo from the main manufacturer. As well the packaging is branded with the logo and the genuine part number. That quality level leads the highest quality and price.
ORIGINAL EQUIPMENT MANUFACTURER PARTS (OEM) are manufactured by an accredited sub manufacturer. The parts are branded with a stamp or logo from the sub manufacturer. Even the packaging is different to the main manufacturer. The price level is below from genuine.