Nature's Calling Cat Litter offers incredibly effective odour control that's not only fast clumping and low maintenance but also 100% natural and totally biodegradable so that it's great for the environment too. What's the secret? Nature's Calling is made from the re-claimed lining of walnut shells. Independent laboratory tests compared this fibrous material with other leading cat litter brands and found that it was much more effective at absorbing and neutralizing ammonia. Not only is it incredibly effective at absorbing ammonia and neutralizing odour, but it also clumps quickly on contact - making the removal of those unwanted lumps a breeze. All of which means there is less waste so even the smallest pack of Nature's Calling could last up to 30 days before the whole litter tray needs changing. Environmentally friendly - 100% natural and biodegrable Made entirely from renewable walnut shell linings Fast clumping and odour neutralising Clumps after just 15 minutes Virtually dust-free Doesn't stick to paws 100% free from artificial additives and chemicals Flushable