The undersigned hereby certifies that all merchandise purchased will be exempt, for the reason given below, from State, County, or City Taxes, commonly referred to as Sales and/ or Use Tax, Gross Receipts Tax, etc. It is agreed that the undersigned will be responsible for the tax in the event any of such purchases are held to be taxable. This certificate shall be considered a part of each order unless otherwise specified. This certificate shall be good until revoked in writing.