41 fl.oz. Black Cast Iron Teapot JANG with Filter. The Bredemeijer® Jang is the perfect Japanese model cast iron teapot. Its superior construction and durable enamel interior ensure that the temperature and flavour of the tea are retained for a longer period of time. The Jang is available in either a 3.4 or 5 cup version and is supplied with a stainless steel tea filter.