This paper rack is designed to hold large amount of forms, letters or documents in a minimum of space and also design to be be easy to grab a form when needed. It was designed for A4 sheets 210 x 297mm but US letter should also fit 216 x 355mm as the openings are 220mm wide.
The material is 3mm clear acrylic but you could use any 3mm material, such as MDF or aluminum.
As the project is too large to fit in the small laser cutter I have access to I cut it out on CNC router, which worked well but requires a little cleaning up of the edges.