GenF20 has a 60 day money back guarantee that makes it practically impossible for you to lose.

As per to their site, all you need to do is try out GenF20 for 60 days, and if for any reason you’re not satisfied with GenF20, all you need to do is return the unused portion in the original bottle within 67 days, and you will be refunded 100% of the product purchase price excluding shipping and handling fees.  The 67 days is the combination of the 60 day trial period + a week’s allowance for return shipping.

I think this is a great deal that they are offering, and they also extend the offer with multiple bottle purchases. Just return the first 2 empty bottles plus all the unused bottles within 67 days, and you will be refunded.

Get the full and complete details of the guarantee here.