Staresso Dosing Ring + Coffee Tamper Set for SP200 & SP200M The dosing ring design to made doing your coffee less mess. This is particularly useful with a doserless grinder, when trying to direct the grinder output into your portafilter. It’s basically a mini-funnel that sits on top of your portafilter basket. Model no: T2 Material: SUS304 Stainless Steel, Aluminium alloy Tamper diameter: 37mm