Upgrades
Remember:
Every module has several levels of update and their amount varies from tank to tank.
After module purchase goes the delivery.
The delivery takes some time. The higher level of module is, the longer it takes to deliver it.
If you don't want to wait, you can speed up the delivery.
When the module is delivered, it automatically installs on vehicle.
Purchase > Delivery> Automatic installation
MAIN GUN

This upgrade lets you increase maximum damage of your vehicle.
AUTOLOADER

The more this module is upgraded, the higher your fire speed is.
ARMOR

If you upgrade your armor, your vehicle can stand more hits.
ENGINE

High vehicle speed lets you immediately react on enemy attacks.
CHASSIS

Chassis upgrade increases your manoeuvring ability.