From the Super Mario Wiki
The Button tires are an unlockable set of tires that first appears in Mario Kart 8 and Mario Kart 8 Deluxe. They are statistically identical to the Roller, Azure Roller, and Leaf Tires; they offer a high acceleration boost and a handling boost at the cost of mitigating speed, weight, and traction. The only difference is its appearance and size. The Button tires look like light brown buttons with distinctive red yarn forming an "X" in the center.
In Mario Kart 8 Deluxe, A CPU Female Villager and Toadette often uses this tire alongside the Teddy Buggy body, and the Button tires have had their stats altered, now only sharing them with the Leaf Tires. They now reduce the water speed, air speed, acceleration, ground handling, water handling, air handling, traction and miniturbo stats to some extent, while the anti-gravity speed stat is improved.
Mario Kart 8
Mario Kart 8 Deluxe
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