IIRC they're used principally for olive oil in Italy, they have been discussed at length though I can't remember where Derek Spedding of the Craft Brewers Association had a holiday in Italy and had his picture taken next to these, they were outside a shop, on the pavement, for sale :grin:
Stainless conicals have been imported from Italy and are available at the brew shop in Stockport, see here
IMO, due to the way they're made, I didn't buy. The 'take offs' for the ball valves are not sanitary, and could well lead to infection.
I'll try and find the link to the pics I took of the conicals...one mo :thumb: