Buy Rocket League Credits game) to procure

At present, players can buy plunder boxes (known as cartons in the Buy Rocket League Credits game) to procure custom wheels, decals or vehicles to use in the game.

 There's no assurance what you'll get when you open another crate, each containing one thing from a lot of expected contributions with different degrees of extraordinariness. 

All that is www.lolga.com evolving. Psyonix, the game's designer, and parent organization Epic Games.