This dosing funnel is 53mm is sized to fit La San Marco, Dalla Corte, La Spaziale, some Quick Mill, Olympia Maximatic (large group), and others that use a 53/54mm basket.
The collar is 5mm tall from the bottom edge to the beginning of the flare, and the exact measurement of the collar is 53.5mm in diameter. The funnel has an outside diameter at the rim of 80mm.
