Gauntlet

Gauntlets are a type of currency found in Plants vs. Zombies 2. They are used to start a match in one of this game's game modes, called Battlez. You can buy them with gems in the Store or win them in Battlez. You can also get two free gauntlets each day from FREE GAUNTLETS by watching ads.

Gauntlets can be obtained in mass numbers at higher reward streaks. They can easily be obtained in huge amounts from the store. Each gauntlet is worth 5 gems, as you will be able to see from the store (4 gauntlets=20 gems). More value is gained when buying more gauntlets (for example, 4 cost 20, but 16 cost 75=5 gems saved!).

There is a common glitch with the gauntlets that makes its sign/image at the top of Battlez turn into a pink X.

Origins
Gauntlets appear to look like a hand of a Knight Zombie, despite the fact that Knight Zombies only receive armor on their heads and shoulders.