We pledge to '30-day money-back guarantee' policy. Before returning the item, please consider contacting us first, giving us the opportunity to correct the issue for you, or to simply hear your feedback. If you purchased your Davis product directly from us, you may mail it back to us. Mail the product with the reason for its return to: Davis Instruments Corp., 3465 Diablo Ave, Hayward, California 94545 USA. Shipping charges are not refundable. If you purchased your Davis product from one of our resellers, please contact the reseller for returns.