MTG Backpack TCG Card Storage - TCG Backpack for Deck Boxes, Sleeved Cards, Playmats, MTG Accessories

Q: The dimensions listed are 12.5 x 5 x 21 inches. Are these the dimensions of the backpack as a whole? If so, what are the interior dimensions?

Interior dimensions are 11.5 x 4 x 19. Interior is large enough to hold 24 standard Magic decks or 15 Commander decks. There is enough room for anything you may want.

Q: Would the laptop sleeve fit a nine pocket trade binder?

It fit mine. I use an Ultra Pro nine pocket 360 cards sidesleeve binder.

Q: Is there a way to get more dividers?

camera bag Velcro dividers. got a bundle of all different lengths and style of divider works great.

Q: How customizable is the backpack? I would love to be able to switch from carrying my magic cards to carrying DnD books

There is some space so you may also be able to have a book or two in with your magic cards too but you can move or remove all the spacers in the main part of the bag as well so it should work well for swapping between the two