I wanted to mail my buddy a Flat Rate Box with some fragile contents, so I made an insert for it. This is v1.1, v1.0 was a little too tall, This version should be perfect, since I've made it 1mm smaller. I overwrapped mine, and measured it at about 1.75" before I took 1mm off of it, so assuming you don't wrap your box 2-3 times, this will fit Perfectly inside of a flat rate usps box. The walls are 1/8" thick, because the box is measured in fractional english, but, I designed and modified all the features in metric. The lid lid fits against the chamfer, and seals the lip nicely. Internal space is ~1.4" H, 5 1/8"w x 7" L (sorry, the files are exported on their side, I'll eventually fix that) I'll probably ship another of these soon and update to 1.2 with what I learn from the second shipment.