The Endge is theOut Of goggle in which changing the lens is less intuitive, but once the mechanism is clear the whole changing will result quick as well.
To take off the lens we want to change we pull the upper part of the frame up so unlock the lens from the joins. Done this the lens will come out easily simply pulling.
To mount the new lens we start from the now, inserting it in the slot in the lens one side first and the the other, therefore not in a symmetrical way, but first either the left or the right side.
Now we pass to one of the low joins and we insert it paying attention to insert the lens in the right slot down deep. Once the first join is inserted we go to click in the correspondent upper join, moving the frame horizontally while pushing the lens in the slot, trying to push it deep down also pushing with a certain decision.
Then, to finish, we apply the same procedure for the other side and the goggle is ready to be worn.