How do you change lens in endura shark sunglasses?

I had the same question, so I asked Endura. * With your thumb and forefinger, grasp the frame firmly at the centre of the glasses (above the nose piece). * With the other hand, grasp one of the lenses close to the nose piece between thumb and forefinger. * Pull the lenses downwards firmly away from the frame. They should release with a bit of effort. To insert other lenses, reverse the process... * Align the new lenses to the slot in the frame. * Hold the lens between thumb and forefinger close to the nose piece. * Whilst holding the frame firmly at the centre with the other hand, push the lenses firmly upwards into the frame. It should click into place.