Poked around looking at Gromwell Root suppliers. Maybe where the Amazon sellers get it from?

Notice the Shikonin range varies wildly 0.5% - 98% as one example.

Tollovid Max has very little. That's because it's an extract and they can extract what is works and not what doesn't or...

Buying some 'stuff' on Amazon, Alibaba, etc. is rolling the dice.

Maybe better off finding a local supplier for 'experiments' related to health

https://www.alibaba.com/showroom/gromwell+roo...leryList=G

https://m.made-in-china.com/product/Top-Quali...01422.html