Quoted from John_I:Personally I just use two layers of mylar now, but the Cliffy's work fine too now that the right hand side is long enough use two screws instead of one. The earlier model with one screw used to move around and rotate outward; it was a pain...
When you take off the apron, take a look at the playfield under the front edge of the apron. You will most likely notice the metal apron has been cutting into the clear and playfield. I 3D print my own protectors to slide onto the apron, but there is a really nice product in the Pinside store which is nicer than the ones I make.
https://pinside.com/pinball/market/shops/1192-apron-envy/04424-apron-edgers-stern-metal-aprons-with-riveted-eye-bolts
I didn't see where a second screw would go at the top of the right side. There is a hole but no screw is anywhere in that area that would come up. There is adhesive at the top to hold it.