by customer originally posted on AudiogoN:

Just recieved two pairs of CV181-Z ‘A’ Tubes from Grant Fidelity. They came in nice boxes, way over packed, and quick. I then tested them on my own Amplitrex 1000 tube tester, and, folks, these are the most closely matched tubes I have ever bought.

full thread here:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1248723961&read&keyw&zzshuguang+treasure