Just finished putting this beauty together and was pleasantly impressed with how easily it went together (my husband and I didn’t argue once!) the quality of the materials, and the accuracy of the drill holes, everything fit perfectly. They included extra supports for the back making it even more sturdy. (pictured). Each “mail slot” is 9.5” wide, so it has plenty of space for slightly oversized pieces. I love this organizer. I may be ordering more. Shhhh-Don’t tell my husband!