orta-Pak Express deodorizer sachets utilise the Walex Wave2 odour control technology to deliver unsurpassed long-term odour prevention for all caravan, boat and recirculating toilet applications. Plus Porta-Pak Express provides the ease of use and convenience of a pre-packaged portion control system. The commercial strength water soluble sachet disperses quickly into water and will not clog pipes, pumps or valves. Continued use of Porta-Pak Express will keep your toilet odour free and hassle free. No need for messy liquids or chalky tablets.