These are membrane boxes (brand : CrystalAir, Compression Box) designed to hold sensitive electronic components. I received a meteorite collection that belonged to a retired NASA engineer who worked on the Hubble Space Telescope project. He repurposed these to hold his meteorites. These are high quality and have several features that make them ideal for housing rare or fragile meteorite/mineral specimens. Note, I could not find a retail vendor for these boxes to compare prices. I have no idea what these sell for now. You can read more about them at this link - http://www.ade-usa.com/products_crystalair_4x3.html
Note, these are the 4 x 3 inches size. These boxes are lightly used and the membrane inside may have some minor deformations or discolorations which does not effect their integrity or use.
Refer to the photos. The black centimeter cube is shown for scale and is not included. You are purchasing all of the boxes shown (five).
