{
  "type": "sophisticatedbackpacks:backpack_upgrade",
  "conditions": [
    {
      "type": "sophisticatedcore:item_enabled",
      "itemRegistryName": "sophisticatedbackpacks:iron_backpack"
    }
  ],
  "key": {
    "B": {
      "item": "sophisticatedbackpacks:copper_backpack"
    },
    "I": {
      "tag": "gt:plates/iron"
    }
  },
  "pattern": [
    " I ",
    "IBI",
    " I "
  ],
  "result": {
    "item": "sophisticatedbackpacks:iron_backpack"
  }
}