Editor recommended because this is the officially named Prestige Attachment for CARBON 57. It is not labeled BEST. Tradeoffs are quoted from official launch copy.

CARBON 57
MagazineMFS Renown Plus Extended MagReach maximum Weapon Level and Prestige the weapon.
Improved Extended Mag that increases ammo capacity and drastically improves base, aiming, and sprinting movement speed at the cost of damage range.
Attachments 1
- MagazineMFS Renown Plus Extended MagReach maximum Weapon Level and Prestige the weapon.
Improved Extended Mag that increases ammo capacity and drastically improves base, aiming, and sprinting movement speed at the cost of damage range.
Alternatives
- Base weapon / no prestige attachmentKeep the base gunsmith path if you do not want the official prestige tradeoff quoted above.
Evidence basis: Source
For streamers: add this as an OBS Browser Source — stream widget
Recommended · bo7-carbon-57-prestige-launch