The equipped monster gains 500 ATK, also it is treated as a "Ninja" monster.
You can only use each of the following effects of "Ninjitsu Art Tool - Iron Digger" once per turn.
You can banish 1 "Ninja" monster from your GY, then target 1 card on the field; destroy it.
If this card is sent from the field to the GY: You can target 1 of your banished "Ninja" monsters; add it to your hand or Special Summon it in face-down Defense Position.