Upgrades
Source GM Core pg. 136
Many items can be improved by installing upgrades into an item's unused upgrade slot. Upgrades are a fun and versatile way to customize weapons and armor without throwing away the previous items. Each should be fairly simple, especially at lower levels, because combining upgrades can make things overcomplicated. Compare to other properties to determine the right level.
While the upgrades in Player Core are exclusively for armor and weapons, you can design bespoke upgrades that apply to other items when necessary. Upgrades that go on items other than weapons and armor should define that the item can only use one upgrade, as only armor and weapons can get additional upgrade slots. In most cases, you're better off designing a higher grade for the item or designing a bespoke item that functions alongside other specific equipment, such as the reusable grenade shell.
While the upgrades in Player Core are exclusively for armor and weapons, you can design bespoke upgrades that apply to other items when necessary. Upgrades that go on items other than weapons and armor should define that the item can only use one upgrade, as only armor and weapons can get additional upgrade slots. In most cases, you're better off designing a higher grade for the item or designing a bespoke item that functions alongside other specific equipment, such as the reusable grenade shell.