The Arcane Spirit Shield is part of the Spirit Shield set. Unike the Elysian and Divine Spirit Shields , the Arcane Spirit Shield does not reduce all incoming damage by 30%. It requires 75 Defence, 70 Prayer and 65 Magic to wield.
The Spirit shields follow a certain "combat triangle": Arcane for Magic, Divine spirit shield for Melee, and Elysian spirit shield for Ranged. So for attacking any monster that is Melee based, the Arcane Spirit Shield would be the preferred shield (for defensive use) rather than the Divine and Elysian Spirit Shields.