First of all, the nose smells, if it is genuine, the torn film has no pungent glue smell.

Second, start paddling.

(1) Scrape the adhesive surface of the film with a key, and the color will not fade.

(2) In addition, the membrane should be a pressure mucosa, that is, it needs to be constantly pressed by external forces to show adhesion. You can take a corner of the waste film and tear off the inner layer and put it between your fingers to feel it. If there is no adhesion, it is a real membrane, if it sticks to the hand, it is a fake membrane.

Third, acceptance.

(1) See if the product can provide a film warranty card;

(2) The edge of the watermark on the real film is clear and the outline is clear. The watermark on the fake film has blurred edges and unclear handwriting; After the real film is attached to the window, the lines on the surface of the film are fine and smooth, and the fake film looks like skin lines and rough.

Fourth, authorized users of the construction workshop can provide testing services (laboratory standard testing by spectrum analyzer).

I hope my answer is helpful to you.