Eco Period Cup & Steriliser Bundle This bundle includes an Eco Cup menstrual cup, and a microwaveable menstrual cup steriliser. Microwaveable steriliser makes cleaning a breeze and doubles as a carry / storage case to keep your cup clean while travelling or in your bathroom. About the Eco Period Cup Our cups come in a choice of XS, S, and L. XS is generally recommended for younger women who’ve never given birth, whilst Small and Large have a slightly larger capacity and diameter. See notes further below about choosing a size. Features: * Up to 12 hours protection between emptying (but we recommend emptying and checking more often to get to know your flow and needs).