The Ordinary EUK 134 0.1% is a mimetic of superoxide dismutase and catalase, forming an exceptionally rare self-regenerating molecule that scavenges superoxide free radicals, eliminates hydrogen peroxide and converts reactive oxygen species into water and oxygen. While it has been around for many years, very few products on the market do use this truly superb antioxidant which can regenerate itself to offer round-the-clock antioxidant support. The only issue with EUK 134 is that it must not be used immediately with strong acids such as suspensions of Ascorbic Acid. Strong acids will completely destroy EUK 134 which is based on manganese. Shield your skin from harmful environmental aggressors with the EUK 134 Serum 0.1% from The Ordinary. A lightweight serum formulated with an extremely high concentration of EUK 134 – a self-regenerating molecule – the antioxidant-packed formula helps to neutralise harmful particles including smoke, pollution and UV light before they oxidise on the skin and cause damage and signs of ageing. An antioxidant formula that brightens your skin.