Are ariston and Biasi Parts Interchangeable?

[karry]

I need to change the drain valve on a Biasi Prisma combi.

A local supplier has one for an Ariston that he thinks will fit.

Not only does it look like the original one that came with the Prisma but its also only a third of the price of the Biasi one.

I changed the original one many years ago with a replacement from Biasi.

The original had a round Knob to open and shut the valve, the replacement is like a radiator bleed valve and needs a radiator bleed key.

It will save me hassle of removing the broken one, taking to the shop to compare if someone can confirm either way

Thanks