The slot list is what Activision publishes for each weapon. Which attachments you can buy for a slot, and what each one does to the five stats, is a separate question — the Gunsmith in game will tell you that part. Launchers and the knife have no slots at all: the guide says they only change their Appearance.
Why the slot list matters
The Overkill perk is the obvious example: it takes the place of your Secondary weapon, so a loadout built around a second primary has to work without one. Beyond that, the slot list decides which of your unlocked attachments you can even fit, and because attachments unlock once and work everywhere, a weapon missing a slot you have invested in is a weapon that will never reach the build you wanted.
The slot types
Launch weapons accept a specific subset. A Kastov 762 takes Optic, Muzzle, Barrel, Underbarrel, Magazine, Rear Grip, Stock, Laser and Ammunition. The Oden swaps Rear Grip for a Comb. These are the officially published lists, per weapon.
Why some weapons show no slots
Activision is explicit about this one: "Gunsmith is available for Pistols, while Launchers can only change their Appearance (Camos, Decals, and Stickers)," and Melee Weapons only change their Appearance as well. The four launchers and the FSS Carbon Edge 1095 knife therefore have an Attachment list of N/A, which is not missing data — it is the rule.
WHAT EACH SLOT DOES ↗ BUILD A CLASS ↗
Where this comes from
Reviewed October 22, 2026. Quoted text is from Activision’s own published material. Advice that is this site’s own judgement is labelled as such.