The short version
7 companies supply this market — a reasonable cushion if one runs into trouble. The generic price has fallen 46% in a year, to $0.8320 per unit — and generics that get this cheap tend to get abandoned rather than defended. The brand (Banzel) runs $18.90 per unit — 17× more. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
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