The latest and updated 9th edition versions of the Textbook and Workbook are now available for purchase as a bundle. These books are essential for individuals who are looking to become a Certified Registered Central Service Technician (CRCST). The set is in pristine condition, with no creases or marks. Please note that the price is firm and the books are being sold as a bundle. For more information, please visit myhspa.org. Comes From a Smoke-Free Home