Yes, all upgrades are permanent, including trap upgrades. If you upgrade a saw to level 5, whenever you get a base that can be equipped with it, your saw will be level 5, not level 1.
Are trap upgrades permanent?
Last Updated: 339d
Yes, all upgrades are permanent, including trap upgrades. If you upgrade a saw to level 5, whenever you get a base that can be equipped with it, your saw will be level 5, not level 1.