Abstract: A handheld cylinder (103) capable of containing hot water. The cylinder has a pump 105 for pressurised the headspace above the hot water with air. The cylinder (103) also has a spout (107) which can be open and closed by a valve (500). When the pressurised air which has been warmed by the hot water is released from the spout (107), the air can be directed into a body of milk to swirl the milk in its container (109) to cause frothing and foaming of the milk.

Abstract: A method of authenticating the warranty of a product is disclosed. The method comprises the steps of providing a product; the product placed in a packaging; the packaging is tagged with a product tracking device which is accessible for being read by a scanner; an authentication device placed inside the packing to be physically out of reach unless the packaging has been opened; the authentication device contains an authentication code; when the authentication code in the device is read by a scanner and sent to an authentication server to authenticate the product, the server generates a warranty code linked to an account of the first buyer of the product.