Just Finished the assembly of my 120 gallon box. My thoughts; (1) Have at least two people assemble to make it easier, (2) Read the instructions ENTIRELY before beginning assembly! (3) *** MOST IMPORTANT!!!*** Do NOT snap the SECOND end piece into place until you have installed the two top long metal reinforcement pieces in place!!!! I can not state this strongly enough: After installing the first end piece into the front and back pieces, \"DO NOT SNAP the SECOND END PIECE INTO PLACE UNTIL AFTER YOU HAVE INSTALLED BOTH METAL REINFORCEMENT PIECES INTO THE TOP OF THE FRONT AND BACK PIECES!!!! In my haste to assemble the box I snapped in the second end piece BEFORE inserting the long metal reinforcement pieces. BIG MISTAKE!!! I had to use a hack saw to remedy my mistake. (I cut the metal reinforcement pieces shorter (maybe 1/2 inch), pried the second end piece back (careful, breaks easily!) and forcing the metal piece into it's slot. Worked but not advisable as it may weaken the box? (4) Surprise! There are many screws involved in assembly of this box, it does not just snap together. (5) The Internal dimensions of my 120 gallon box: 52 1/2 inches Long, 23 1/4 inches wide, 21 inches deep (give or take) The Lid was 1 5/8 inches thick, Front piece 1 3/8 inches thick, Back piece 1 3/4 inches thick with the hinges. (6) I was able to tightly 'stuff' eight (24\" sq X 4\" thick) cushions (enough for four chairs, seat and back) with a couple of inches to spare on the end (give or take). You would assume (mathematically) that you could lay in another 4\" thick cushion, you can not! Do to the stuffing I suppose, there is only about 3 1/2 inches of empty space on top and another cushion would hold open the lid, unless possibly you could force it shut and latch it somehow? (7) Just my opinion, but I kind of doubt this would hold up three American size adults for an extended period. (660 lbs? +/_ ) 8) Looks good. How long will it last? Time will tell.