absolutely the the best customer service and interaction that I have ever received. I have never used peptides. had been looking thru a bunch of different sites and did not have a clue as to what to order or from what site cus. Some of them are out of the country and the ones in the USA were out of stock and to expensive, I had already almost given up looking at all the different peptides sites but this morning a was looking at Facebook and a saw an ad for certified peptides and I decided to go to the site and started looking at all the different items when a service representative ( Rebecca ) come on the line and after about 2 hours and 100+ questions Rebecca helped place my 1st order of NAD+ and IPA & CJC.. when I placed the order I made a mistake and Rebecca transfer me to Jason and corrected my mistake and they helped me with the specials they had and gave me a 20% discount. Absolutely the best; cant wait to get my order and start using it.. thx….