FYI, OEM parts are original parts. i experienced buying both OEM and genuine parts from the same manufacturer and the quality are the same. For example, I have 2 same BMW model, I bought genuine brake pads for one of it and Textar brand (OEM) brake pads for the other. The genuine brake pads are also made by Textar. Compared the quality, they are the same.

I experienced buying many other OEM and genuine parts. Normally, the only thing different are the labelling and the packaging.

Some people (including mechanics and sellers) are confused between OEM and Thirdy-party.