Pokemon GO Upgrade Items and Components
An upgrade item level upgrade (read this post from www.google.co.vi) is a special item that makes certain Pokemon develop. The upgrade can be obtained by spinning a photo disc and is sometimes offered as a reward during Pokemon GO events.
Upgrades can be applied to weapons, armors, trinkets, and gathering tools in order to raise their Best item upgrade level. The upgrade costs Flightstones or crests based on the type of item.
Upgrade components
Upgrade components can be inserted into weapons, armor trinkets, trinkets, or gathering tools to give attribute bonuses or additional effects while the equipment is being utilized. Upgrade components are only available on equipment with an upgrade slot available. Most upgrade components also require that the item to be upgraded is above a certain level. Certain upgrade items also come with special visual effects when they are added to an equipment piece.