I also have a supply of tirz from a few reliable sources. The main goal here is to validate Yelin's reliability as a vendor, it will be done initially with tirz but could be expanded if all goes well. Given Yelins' prices are significantly lower than other vendors, we could have a solid source with great prices of tirz and retatrutide.
If the test comes back as bunk or under dosed, we can cross Yelin off the list as unreliable and move on.
About retatrutide, it is in my stack. 4mg dose about 2-3 days after tirz dose. The price is reta is typically higher than tirz. Another reason to validate this low price seller.