This promotional offer applies only to the listed variants starting with 497157xx xx variant identifier applaws natures calling is a 100 natural and biodegradable clumping cat litter made from the lining of the walnut shell this innovative blend of fibrous material has been proven to effectively absorb and neutralise odour the litter begins to clump on contact with liquid and forms hard lumps within just 15 minutes applaws natures calling is virtually dust free the granules dont