Equip Card

An "Equip Card" is any card that is equipped to a face-up monster on the field. Spell Cards with the Equip Icon are the most common type of Equip Card, and are officially called Equip Spell Cards. They are treated as both Spell Cards] (They would be destroyed by the effect of "Heavy Storm") and Equip Cards (for purposes such as "Gearfried the Swordmaster".) Other cards may become Equip Cards though card effects, like with "Sword Hunter" or Union Monsters. Whenever a Monster Card becomes an Equip Card, it is treated as an Equip Spell Card, and is no longer a Monster Card. So a "Dark Magician" equipped to your "Sword Hunter" as an Equip Card could be destroyed by "Heavy Storm" but not by "Tribute to the Doomed".

Some Trap Cards, like "Blast with Chain", can also become Equip Cards. These cards are considered Equip Cards but are NOT Equip Spell Cards. This means that it is a Trap Card (and could be destroyed by "Remove Trap") and an Equip Card (for purposes such as "Gearfried the Swordmaster"). It is not a Spell Card, and cannot be destroyed by "De-Spell".