What it is and why it's in the formula
Vitamin E (as Tocopheryl Acetate) is an antioxidant that's a near-universal addition to nail and skin oil blends. Beyond its own conditioning properties, it's often included to help stabilize a formula's other plant oils. It's one of the two headline ingredients called out on the product label itself, alongside the overall '16 natural oils' positioning.
Where it fits in the full formula
Vitamin E is one of 16 ingredients disclosed openly on the PureNail Pro label — none of the formula sits behind vague "proprietary blend" wording. You can see the complete breakdown, including which oils pair with it, on the full ingredients page.