ITEM NAME:Photoresist Blue Paint + Developer + Etchant + Resist Remover for DIY PCB Kit.You are buying one bottle 100g Photoresist Anti-etching Blue Paint + 20g Developer + 100g Odorless Etchant + 10g Resist Remover for DIY PCB & Photo Etched. The best diluent can be banana oil or lacquer thinner.