Our Certified Laboratory utilizes Environmental Protection Agency Certified Technicians. we are Department of Transportation Inspected & in full compliance with all Hazardous Materials Shipping & handling requirements pursuant to USDOT 49 CFR Parts 171–180. E.P.A. Refrigerant Sales Restrictions apply herein; https://www.epa.gov/section608/refrigerant-sales-restriction. Sales allowed only to E.P.A. Certified Technicians. *Purchases for Resale do not require any certification. If you purchase any products containing refrigerant from us, you are affirming one or the other. We do not allow returns on any refrigerant due to change of possession liability concerns and hazardous materials shipping requirements. all the products listed on this site are in stock and ship the same day if purchased by 12:00pm central standard time.