Short answer: A 60-day guarantee is advertised, and it is genuinely the most useful thing on the offer — given that the research window for berberine runs past 8 weeks, you need roughly that long to judge anything at all.
Why this specific overlap matters
NCCIH's berberine research window was 8+ weeks — 60 days is almost exactly that same timeframe, giving you a genuine chance to evaluate the formula against the same window the underlying research used.
Why the specifics are set by the retailer, not this page
The return window for requesting a refund, the return address, whether the bottles must be unopened, and who pays return postage are all set by the retailer rather than by this page.
Why a two-bottle pack is roughly the minimum for a fair trial
Given the 8-week research window, a two-bottle (60-day) pack is roughly the minimum quantity needed to actually complete a fair evaluation period.
Check the packages
60-day guarantee advertised — confirm terms at checkout.
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