Adjustable Book Page Holder

Some books never stay open, their pages keep turning continuously whether you want it or not. This can be caused by the material of the book itself or by the wind. 
To prevent these pages from turning i made an adjustable book page holder. The holder makes it even possible to turn the pages while the rest of the pages are held.
The book page holder fits different book sizes because of the hinge system that makes it possible to adjust it.

Materials:
-Two plastic, metal or wooden pieces that form the base. (I cut two plastic S-forms out with a laser cutter)
-4 little bars of aluminum 
-4 marbles
-1 bolt and 1 nut

The making process:
1) Cut out or saw out 2 S-forms, that each contain a circle in the middle
2) Mill out the circles (until you reach half the thickness then the rest of the S-form)
3) Drill a hole in the middle of the circles (the hole has to have the same size as the bolt)
4) Drill a hole on each end of the S-form (the hole has to have the same size as the little bars)
5) Bent the 4 little bars 90°
6) Glue the marbles onto the little bars with epoxy glue
7) Fill each hole with one little bar and position the marbles so that they 'look' to each other
8) Fix the 4 little bars with epoxy glue
9) Fix the two S-forms by using the bolt and the nut
10) Enjoy your reading, whether it is for studying, cooking or anything else!