Psyonix have announced that the next update for Rocket League will introduce an expanded version of their new Item Attribute System which allows users to get special item drops after playing online matches.
This expansion will come in the form of a rarity system and a trade-in system for users who have got multiple drops of the same item. Each rare decal or very rare boost trail can only be acquired through online matches and not earned anywhere else.
For users who have acquired a number of the same items, you can now trade in your items for a better rarity item. When the new update rolls out you will be able to trade in five uncommon or rare duplicates for an item of the next-highest rarity.

The menu for trading in your items will be found under “manage inventory” in the garage menu. After that, just select all the items you want to trade in, hit confirm and get your new, rarer item.
Soure: Psyonix
Lewis is a games journalist, freelance gaming and consumer-tech journalist. They contributed 344 articles to ICXM between 2015–2017, focused on opinion pieces, game reviews, Windows and PC, and Xbox news: has since served as Editor-in-Chief at StealthOptional and Gaming Editor at MSPoweruser, with bylines at Gfinity Esports and FRVR.