My variant of a YuGiOh Deckbox.
There are holes for magnets with 1cm diameter and about 1mm thickness. Lid magnet neends glue to hold, box on can be inserted and should hold by itself.
I use double sleeves for my extra deck. Most deckboxes only consider only one type of sleeves, so I created this little box. 
It's not perfect and I will update it now and then.
It should hold at least 40 + 15 cards (regulard jap. sized sleeves) and 15 Extradeck cards (double sleeved Standard size).