Blue Diamond’s “2L When Nature Calls Toilet Fluid” is a completely formaldehyde free concentrated toilet fluid, designed to leave your chemical toilet (cassette toilets and waste holding tanks, typically found within caravans, motorhomes and boats) smelling pleasantly perfumed and offering plenty of use with the 2L of volume. Safe to use and long-lasting; this formula is great for use in hard water areas and ideal for green fluid only campsites. This environmentally-friendly product is biodegradable and gives off a strong, medicated fragrance, making it perfect for eco-lovers!