Forever 21 in US has extra 30% off their sale item with coupon TAKE30. Please note that Ziptango charges 11% from the total cost (total mark up is 20% from the final price because there is 9% US sales tax) + AU shipping cost.
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Forever 21 Sale
Remember that when US have a season sale, AU is entering that season, so Forever 21 is having their summer cloth sales, AU is entering it in couple months. And ziptango can ship all your shopping into one shipping box so you only pay one shipping fee + AU has a free import tax for up to AUD1000 per shipment.