Its from an extremely reputable vendor (btm) The purity seems to be extremely high, and wow I had the best day of my life yesterday. The problem is they sent me 100mg less than they were supposed to. I payed a hefty amount for 500mg, and to get jipped 100mg from such a reputable vendor made me a little upset. I knew they were really low on product tried to sell as much for as little as they could. I emailed them about it, and all I can hope is they give me a free credit voucher!! Which is what I would expect from such a reputable vendor. Was very surprised that happened!!