Jaysuing Vitamin C Brightening eye serum

Shares niacinamide but uses ascorbyl glucoside instead of pure ascorbic acid, so the vitamin C form and likely potency differ from the source's straight ascorbic acid.

Has niacinamide but swaps ascorbic acid for sodium ascorbyl phosphate, a weaker/more stable vitamin C derivative, plus it's a sunscreen-loaded day cream rather than a targeted brightening serum.

Contains niacinamide and hyaluronic acid like the source, but uses two derivative forms of vitamin C (ethyl ascorbic acid, tetrahexyldecyl ascorbate) rather than straight ascorbic acid, and adds many extra actives not in the source.

Matches on pure ascorbic acid, a real plus, but it's missing niacinamide entirely and is a premium-priced serum, not a budget dupe.

Only shares niacinamide; it has no vitamin C at all, which is the headline active in the source's name and formula.