Want to prevent unwanted and unpleasant smells coming from your drains? This Thetford Grey Water Fresh Concentrate is the perfect solution. It is a strong, concentrated, effective fluid which will keep your grey water cleaner and fresher for longer. Conveniently coming in a small sized 800ml bottle, all you require is a mere 80ml dose based on a grey water capacity of 100L. Simply add the concentrate each time you empty your grey water tank. Useful for all RV enthusiasts.