BSP-BSP plumbing question

[rick]

Had to replace a hand basin tap ... Old tap had flexible tails connecting to isolation valves ... the flexy connector ending in 1/2" BSP female

New tap has flexy connector ending in 3/8" BSP female I can find 1/2" BSP Female x 3/8" BSP Male such as:

The male end is fine .... but the female end has no internal rubber washer so wouldn't seal onto the isolation valve. (rough sketch if description not clear)

Is there a 'name' for such an adapter with a washer ...

Sort of assumed something would exist for this ..... or do I need to swap out isolation valves to ones with a 3/8" BSP female thread.

Just extra cost and time (and not my house)

[Fredxx]

They do exist:

Are you sure it's 3/8"? Most service valves like your diagram are designed for use with olive? One for a BSP fitting would be like this: I would probably get a 15mm to 3/8 BSP radiator/tap tail: and fit it into a standard service valve: Using fibre washers where needed.