Field Upgrades are pieces of equipment in Call of Duty: Warzone which can give you a tactical advantage.
You need to manually activate Field Upgrades in order to use them and they have a cooldown time. Some Upgrades take longer than others to recharge. Field Upgrades can be found in Supply Boxes and Loot crates. When you have a specific Field Upgrade, it will show up at the bottom right corner of your screen. You can also set Field Upgrades in your Custom Loadout and then acquire them through Loadout Drops.
You can only use one Field Upgrade in Warzone. This is also true for Modern Warfare until you reach Level 45, unlocking Field Upgrade Pro, allowing you to use two. There are a total of seven Field Upgrades available to choose from in Call of Duty Warzone, with another two that are available in Plunder mode only.
This guide will give you a rundown of all Field Upgrades.
Munitions Box
When you activate this Field Upgrade, you will deploy a box of ammo which you and your squadmates can use to refill your ammo and equipment such as grenades. Shooting the box several times will cause it to explore, so be careful while using it - and keep in mind the tactical uses, since that explosion can harm opponents too.

In order to refill a specific ammo type, equip a weapon of the desired type and then deploy the Munitions Box.









