by darrensandford on Wed Feb 24, 2010 3:48 pm
Right - this one is definitely like the bottom one in your picture. The pointy end is 6mm, the shaft above the inner thread is 7mm.
I suspect that it won't fit your existing valve, as it is too new same as the bottom one. I can still send the entire unit if that would help, assuming it will fit the thread on the boiler.