Coming soon: a new credit card that gives you a 5% cashback bonus after your first spending and repayment is paid off in full.

This new card, called the Infinite Card by Qudian, already has 4,000 users (there are no traditional sign-up bonuses with this card), according to the New York Times.

Free money? Sure sounds good, but there are potentially strings attached. The company is offering a sign-up bonus of $40 after spending $500 within the first 60 days, with a 1% introductory APR until May 31, 2021 (the APR usually is 20.6%) So get your American Express or Discover card (in which the issuer determines whether a cardholder is earning cashback) in hand before you actually take out a cashback card.

Compared to credit cards that offer smaller rewards, Qudian’s Infinite Card could be expensive if you spend too much with it. But who cares?

The Infinite Card from Qudian has some features that debit cards don’t. It’s not just cashback on everything you purchase – it has merit badge rewards, as well. The card uses the Qudian valuation system, which might sound familiar.

Qudian gives monthly rewards points called “Q DuHi” that can be redeemed for cash or gift cards. At the moment, Q DuHi offers 15 categories for shoppers to choose from. If they shop in one of the categories – say a department store that offers Monopoly – Q DuHi can offer 2,000 points, which is a $5 cashback bonus. The company plans to offer more categories. The reward is a little more interesting: the more you spend, the more points you get.

For instance, 10,000 points – which is the equivalent of $20 worth of cashback at most stores – can be redeemed for a $60 gift card at select national retailers. It’s very similar to a store’s loyalty rewards program.

When you use Q DuHi cards, you don’t have to pay transaction or late fees, get your balance automatically transferred into another card, or pay interest on the debt you have. But customers who spend more than $1,500 in any month will be charged 25% an additional annual maintenance fee of $15. That money can’t be used for rewards, however.

Qudian was founded in 2014, but didn’t really hit its stride until 2015. It now has a third of a million active users, with an additional 300,000 coming on board each month.

While this appears to be a hit in China, Qudian wants to reach other markets, and has disclosed its financials to the SEC on the SFX website.

There’s no word yet on the exact denominations of the Infinite Card. Presumably, a lot of the current 4,000 users will end up only using it at existing Qudian stores. With an annual fee of $29 and average spending at more than $2,000, you could see cardholders spending a lot of money.