With the addition of Vitality to accessories, there is no longer a stat distinction between belts and accessories---they have the exact same main stat, vit, primary substat, and secondary substat values, at a particular item level. However, the Edengrace Tassets still cost 6 copies of Book of Resurrection to buy from the gear exchange, whereas other accessories only cost 4 copies. Please adjust the vendor to match the accessory cost.