I’m not sure. I think it was because they could not find a good research grade of cops. I might be wrong but check out this post and see if that’s your answer
I’ve held my lip for years on this, so it wouldn’t harm one of the larger phero retailers out there, which is run by a very good man who happens to have a few disreputable dealers. (and as a retailer, it’s not like he’s had much choice in the matter)
The sad reality is actually that Stone is substandard in every way, shape and form, as all products from dishonest companies are.
Call Sigma-Aldrich on Monday (sigma-aldrich.com ), ask a product manager for chemical A8008, and show them this:
htt…