I purchased 22 (undiluted) and 22S (comes in a 50ml. bottle and is dilluted by the purchaser with 80% isopropanol so there is no hazmat charge) direct from the manufacturer: D.W. Electrochemicals LTD. 97 Newkirk Road North, Unit 3 Richmond Hill, Ontario L4C 3G4 Canada Phone: (905) 508-7500 Fax: (905) 508-7502 Hope this helps someone, Greg Herrmann