Solder ring 15mm x 1/2 inch BSP tap connector.
This is the normal size for sink/basin taps and toilet cistern float valves.
Complete with fibre washer.
Pre-soldered capillary plumbing fitting for copper pipe, made to the European standard EN1254.
You'll need flux for this (available in our store).
BSP (British Standard Pipe Thread) sizes don’t match up with what you would measure using a ruler. Have a look at the BSPT link at the bottom of this page for more information about how plumbing threads are measured.