pH range of 3.2-3.8
Active: Salicylic Acid 2% Inactive: Water, Methylpropanediol, Butylene Glycol (slip agents/penetration enhancers), Camellia Oleifera (Green Tea) Extract (anti-irritant/antioxidant), Polysorbate-20 (solubolizing agent), Sodium Hydroxide (pH balancer), Tetrasodium EDTA (chelating agent).
Paula's Choice BHA liquid exfoliants don't have magical ingredients that are hard to dupe, as they are 2% salicylic acid, a penetration enhancer and green tea extract.
VMV Hypoallergenics toner includes the same ingredients, with the addition of witch hazel water and different emulsifiers. What's important to note is that the pH and percentage of salicylic acid in the dupe product are unknown.