Capital One Shopping

Capital One Shopping is a coupon-and-rewards browser extension with a $5.00 minimum before you can redeem. It is gift-card credit rather than cashback: its terms state that Shopping Rewards "are not money or cash obligations, do not have any monetary value, and may never be redeemed for cash". It also carries the strictest exclusivity clause of the group, because rewards may be unavailable if another rewards extension is merely installed on your browser, whether or not you used it.