Review on Glarks Positioning Woodworking Cabinets Carpenter by Mark Loredo

I made 3 shelves with side panels to put on the floor to put shoes on. I was looking for something to get right angles as I was inserting pocket hole screws into the sides. I use a couple of clips to attach the shelf to the sides before inserting the screws. You have done a great job. Some reviews said this is not true. The best way to make sure they're accurate is to put all 4 together and see if they match. The photo shows what they do.