Thanks for the posts dfk41 and Amberale

Caravel is a gem You can brew very accurately - pop a temp probe like a Thermopen into Lambettthe heating water which isn’t pressurised. Portafiler is tiny. There is no spring so you control extraction pressure. Result is a nice ristretto Two sips at best. Mine sits on the hall console table as it is a work of art - think Lambretta in an espresso machine.

Mine has a bespoke dosing ring