Just be careful with PPD free because very often the substitute is chemically so similar that it's likely to trigger a sensitivity reaction in someone sensitive to PPD.
I'm surprised Refectocil doesnt have PPD in, it's got a bit of a rep for not being suitable for sensitive souls.
I also use London Brow tint which is PPD free. It's a nitrate based tint rather than peroxide so has a different application method and you need training - but it doesn't need a patch test, so it's great for Treatwell bookings from out of town. The black isn't that dark and I don't like it for lashes, but it's really nice for brows and lasts twice as long so I charge extra.
