Optimum-C Formula

Optimum-C Formula and 10 near-identical products are sold under 3 different brand names — a near-twin Formula Twins cluster.

Product	Brand
Optimum-C Formula	Bluebonnet
Optimum-C Formula	Bluebonnet
Buffered Vitamin C	Dr. Clark Research Association Dr. Clark Zentrum
Ester-C 500 mg	American Health
Ester-C 500 mg	American Health
Ester-C 500 mg with Citrus Bioflavoinds	American Health
Ester-C 500 mg with Citrus Bioflavonoids	American Health
Optimum-C Formula	Bluebonnet
Optimum-C Formula	Bluebonnet
Mega Bio-C Formula	Bluebonnet
Mega Bio-C Formula	Bluebonnet