The diameter of the tamper is 51mm, suitable for filter baskets with an inner diameter of 51mm. To ensure that it is suitable for your filter basket, we strongly recommend measuring your filter basket with a pair of nails to get an accurate measurement.
In general, a standard filter basket with an inner diameter of 51mm is slightly larger than 51mm and usually between 51.3mm and 51.5mm. Therefore, the 51mm outer diameter tamper can be pushed into the right depth of the filter basket with a 51mm inner diameter, but it cannot be tucked into the bottom of the filter basket because the inside diameter of the filter basket is 51mm. It is usually smaller than 49mm.