When unbreaking enchantment was applied on non-armor items, its average durability will be new_durability = (lvl + 1) * durability, and lim(lvl -> inf, new_durability) = inf
But if the enchantment was applied on armor items, the formula will be new_durability = (lvl + 1) / (0.6 * lvl + 1), and lim(lvl -> inf, new_durability) = 1.667*durability
Please make all items use the first formula.

nope