Aqua Kem Blue is Thetford's premium waste-holding tank additive. The premium formula offers the best performance and odour control for your cassette toilet.Add 150ml and 2 litres of water to give best results in a 20 litre cassette. Features: Assists in breaking down solids. This formula lasts longer than the GREEN formula, but is NOT suitable if you will empty into Septic Tanks Child proof cap Easy measure markings on side of plastic bottle Specifications Model: T30049 Cequent Lasts 4 to 5 days Add 150ml to 20 litre waste tank Not suitable for septic system or composting toilets Shipping Weight: 1.20 Kgs. Shipping Dimensions: 28 cm x 9 cm x 9 cm.