• Ruby, Sapphire, and Emerald

 > A device that signals an invisible item by sound.

 • FireRed and LeafGreen

 > A device used for finding items. If there is a hidden item nearby when it is used, it emits a signal.

 • HeartGold and SoulSilver

 > It checks for unseen items in the area and makes noise and lights when it finds something.

 • Black and White

 > It checks for unseen items in the area and makes noise and lights when it finds something.

 • Black 2 and White 2

 > It checks for unseen items in the area and makes noise and lights when it finds something.

 • X and Y

 > It searches for hidden items in the area and emits different lights and sounds when it detects something.

 • Generation VII

 > This high-tech machine shows the location of invisible items. It’s attached to the head when in use.