Uppercases slot defines.

code/game/objects/items/storage/fancy.dm

@@ -109,7 +109,7 @@
 	icon_type = "candle"
 	item_state = "candlebox5"
 	throwforce = 2
-	slot_flags = SLOT_BELT
+	slot_flags = ITEM_SLOT_BELT
 	spawn_type = /obj/item/candle
 	fancy_open = TRUE
 
@@ -132,7 +132,7 @@
 	item_state = "cigpacket"
 	w_class = WEIGHT_CLASS_TINY
 	throwforce = 0
-	slot_flags = SLOT_BELT
+	slot_flags = ITEM_SLOT_BELT
 	icon_type = "cigarette"
 	spawn_type = /obj/item/clothing/mask/cigarette/space_cigarette
 
@@ -189,7 +189,7 @@
 		if(M == user && contents.len > 0 && !user.wear_mask)
 			var/obj/item/clothing/mask/cigarette/W = cig
 			SendSignal(COMSIG_TRY_STORAGE_TAKE, W, M)
-			M.equip_to_slot_if_possible(W, slot_wear_mask)
+			M.equip_to_slot_if_possible(W, SLOT_WEAR_MASK)
 			contents -= W
 			to_chat(user, "<span class='notice'>You take a [icon_type] out of the pack.</span>")
 		else