Suitable for all loop-frame Guzzi, I believe. Threads are 12mm diameter x 1mm pitch, spigot diameter 6mm. Made by OMG of Italy. They're a fair amount smaller than the jumbo things Guzzi used as original, but the price is right.
Note: Spigot size is about 6mm. The 1/4" black fuel line I sell will work with a clamp, yet is flexible enough to fit over the 8mm banjo fittings (no clamp required.)
These are NEW parts, of modern materials for modern fuel. Each petcock has circuits for main and reserve. This listing is for the PAIR.