For a full refund, store policy is that you have to return merchandise 2 weeks from the time it was purchased.

店铺对于全额退款的规定是：您必须在购买商品后两周内退货。

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Given REI's liberal merchandise return policy, these frills make economic sense.

FORBES: Backpackers meet the bottom line

Returns without a receipt are subject to the posted return policy, which might result in your receiving only a merchandise credit for the lowest price the item has sold for recently, or possibly no refund or exchange at all.

FORBES: Returning A Gift? What You Need To Know About This Year's Return Policies