Bought first Rolex but having some doubts on authenticity...

[mike123]

Hi all, new to the forum and I brought my first Rolex yesterday--got a black dial Cestello from Tourneau. After returning home, I noticed that there are engravings on the back of the case as I was cleaning it with a cloth. If I remember correctly, I believe Rolex does not make watches with engravings with the exception of 2 watches (forgot names). I panicked at first but then saw that there was a film of plastic on the back casing so I thought perhaps the engravings are actually on the plastic itself and not the case. Does anyone know if that's possible? I didn't want to peel the plastic off because then I will not be able to return it if I have to. Attached is a picture of the engravings. Any input is greatly appreciated. Thanks.