Looks like a good B vitamin source.
Brand/name, please ;-)
They are out of it right now, unfortunately.
My wife’s hair color really is coming back after being white for the past five years. Hair follicles keep producing pigment, but they also start producing hydrogen peroxide that bleaches it out. The B vitamins must interfere with hydrogen peroxide production.
Since I wanted to try it myself, I purchased the supplements below until it gets back in stock. The substitutes give about the same or more of B6, B9 and B12.
https://www.amazon.com/dp/B0938NKV1G?psc=1&ref=ppx_yo2ov_dt_b_product_details
https://www.walmart.com/ip/Spring-Valley-Vitamin-B6-Supplement-100-mg-250-Count/893228?athbdg=L1200