Item Boxes give an Item to any player who runs into them. The Item is randomly determined, but players who are generally in lower places will receive more useful Items, such as a Star or Bullet Bill, and players who are in higher places will get Items that do not help as much as those, such as a Green Shell or a Banana. Racers in middle places will receive Items that are in the middle, such as a Mega Mushroom or a Spiny Shell.
In Balloon Battle or Shine Runners for Mario Kart DS, once a player is eliminated, they can still drive around, and the get Item Boxes themselves as Items. They can be thrown out in front of the Kart and even dragged behind it, and they work exactly like regular Item Boxes.
In Super Mario Kart, item boxes didn't technically exist- they were instead flat panels on the ground, and were called Question Blocks. If one is driven over, the item list would come up, and the items will quickly scroll vertically in a roulette-like fashion; the item it stops on is the item a player can use. Its essence stays throughout the whole series.
The boxes are now 3D (due to the Nintendo 64's support for 3D graphics), are orange and blue in color, and are somewhat diamond shaped. It is impossible to tell from a distance if a Fake Item Box is really an Item Box due to their similar appearances, except for a barely noticeable upside-down question mark for the Fake Item Box. There are still question marks in the middle, and the boxes rotate. They must be driven through rather than over.
Item Boxes are now their signature box-shape. Their 3D model usage is carried over from the previous game, and they cycle through a rainbow palette. They rotate horizontally and make roughly the same sound when they are hit as they do in Mario Kart 64.
Item Boxes went through a drastic redesign in this game. They are now cubes with little squares around them arranged in a checkerboard fashion, and the cubes rotate like they did in the previous games, but the question marks now have a part in the animation, as they bounce every time the cubes turn. Double Dash was also the first Mario Kart game to introduce Item Boxes that move independently around the track. Additionally, Double Item Boxes were added to this game, and obtaining them grant both the driver and the thrower items.
Item Boxes are practically exactly the same as they are in Double Dash!!, bearing a cube design with a rainbow checkerboard pattern and a question mark in the middle. They appear as rainbow squares on the touch screen. Certain Missions require the player to break a certain number of Item Boxes in a given time. Unusually, on DK Pass, there is an Item Box located on a large hill that, regardless of place, will always give a Star, Triple Mushrooms, a single Mushroom, or very rarely, a Red Shell.
The item boxes aren't too different from the previous game, except that the square pattern was changed with a circle pattern on the cubes. The cubes are still animated, having the same animation as in Double Dash!!. However, they do reappear at a slower rate than its predecessors, and it is seen in Toad's Factory that the Item Boxes are made out of normal Brick Blocks.
The Item Boxes reuse most of the same design as their Mario Kart Wii appearance. Unlike Mario Kart DS, they do not appear on the touch screen. While the Item Box in DK Pass remains the same, the Item Boxes in Luigi Raceway and Koopa Troopa Beach that previously gave only Spiny Shells would now give the normal item roulette or a Coin, respectively.
The Item Boxes now have a crystalline grey color and the question mark is larger. The triple items players get from these and the Crazy Eight item, are now activated automatically. The biggest differences between this iteration and Mario Kart 7's version is that players can no longer hold two items at once, and that items appear in the driver's hands. Unlike previous Mario Kart titles, it has a new sound effect for both obtaining and the item roulette.
On certain tracks, the Item Box has different effects or behaviors. In Animal Crossing, there are Item Boxes held up by balloons after the glider ramp, which can obtained by gliding through the physical Box, or popping the balloon, and the item roulette plays a variant of the music when a profile is loaded or saved; the Item Boxes on Hyrule Circuit play the chest opening jingle when cycling the roulette, and the Item Boxes on Urchin Underpass play the stat slot sound from Splatoon when cycling the roulette.
Mario Kart 8 Deluxe brings back the Double Item Boxes from Double Dash!!. Like in said game, players can hold up to two items at once, even if they aren't dragging one, though the second item is held in reserve while the first one is in use.