Rule 152.2

Non-Unit Gear cannot normally become located at a Battlefield unless by some special means. Example: Gear are played to Base unless an effect specifies otherwise. A gear played from Facedown, which is specified to be played to the Battlefield it was played from, will enter at that Battlefield. Gear can also become located at a Battlefield if they are attached to a unit who becomes located at a Battlefield. A Gear that is a Unit can move to a Battlefield. See rule 811. Hidden for more information. See rule 716. Attachment for more information.