used up to 18 oz cereal box hard plastic display case. app. dimensions:  interior: 121/4" x 8 3/8" x 3 1/4".  exterior: 12 5/8' x 8 3/4" x 3 5/8".  holder slides open and closes on beveled edges. case is used and has minor scuffs and few scratches. I used these for my Ripken wheaties boxes back in the day, so they have been around a long time.  new boxes go for 40 to 50 dollars for 1, so here is a chance to get a good used one for a lot less.  winner pays $14 shipping with tracking.