UMITAN TA / VMX pol. is a particular combination of vegetable tannins that veins used in articles vegetable. For vegetable means chrome tanned leathers, like calves, goats, sheep, etc., From retanning with plant extracts to get items like handbags and footwear. UMITAN TA / VMX being a vegetable tannin is sensitive to iron ions, so you should add in the normal production cycle of a sequestering iron type SEQUESTRANT ED CONC.