6 monthly doses. Advanced enzymes + patented bacteria. Works immediately to break down household waste. Works continuously to help prevent septic backups (Along with occasional pumping). No. 1 brand used by septic professionals in their own tanks (Based on a survey of nationally representative septic professionals). Scientifically proven to break down waste. Safe for all pipes & tanks. Scientifically proven to help prevent septic backups. Rid-X contains 100% natural bacteria and enzymes proven to break down household waste and help prevent expensive septic backups. 1st dose. 2nd dose. 3rd dose. 4th dose. 5th dose. Health. Hygiene. Home. www.rid-x.com. Questions? 1-800-228-4722. For more ingredient information, www.rid-x.com. Made in USA.