This is a pack of 10 Fast Pack-XC1 6"x5"x2-1/2" Reusable Anti-Static Mil-Spec Shipping Boxes. The boxes are made to military specifications and compile with ASTM D 5118. They have a burst test rating of 275 lbs per square inch. The interior foam is grey or pink both are anti-static they will be mixed. The boxes are very gently used and in excellent condition. New these boxes sell for over 7.00 each.