Jawbone may be gearing up to ship its UP3 fitness wristband tracker after months of delays, but in a surprising twist, the company already has two other devices up its sleeve: the UP2 and the UP4.

While the UP2 is a scaled down version of the UP3 (announced this fall) in terms of price functionality, and will replace its popular UP24 wearable, the true standout in the new announcement is the UP4 (shown above and below). The UP4 allows users who are American Express customers to make store purchases with just a tap at checkout.

The device, which ships this summer, will cost $179.99 — worth the additional $20, compared to the $159.99 UP3.

The tap-to-pay feature is becoming increasingly popular for smartphones and smartwatches — think Apple Pay and Samsung Pay — but Jawbone is perhaps the first major fitness-focused wearable to take a similar path.

Consider the appeal: You’ve just gone for a run and left your smartphone and wallet at home. Now, you’ll be able to pick up a bottle of water at the grocery store by using UP4. Not only is it cheaper than most smartwatches, it’s considerably lighter and less bulky, too.

The UP4 touts an embeddable NFC chip that makes the transaction process possible. AmEx credentials are added into the existing Jawbone app. While the UP4 will feature a small contactless logo on the wristband, as seen in a rendering image below, the prototype shown in the above images doesn’t include the icon for now.

Jawbone said the UP4 is dedicated to its partnership with American Express and declined to comment on the possibility of including other services like VISA and MasterCard for future-generation wearables.

Meanwhile, the company is phasing out the UP24 with the much slimmer UP2 ($99), a beautiful, sleek device that is 45% smaller than the predecessor. The UP2 is available in black via Jawbone.com now and will come in other shades (including gray) and textures soon.

The newly-announced devices, as well as the UP3 (above), also work with Jawbone’s upgraded Smart Coach software. The feature within Jawbone’s app gives more context to your habits. Instead of just how many hours you’ve slept and how many steps you’ve taken, it shows you how you stack up against others using the app and notices where you can make improvements. For example, if it sees you tend to move more the next day when you get 30 minutes of additional sleep, it will tell you to aim for a specific bedtime.

Jawbone has been taking its time to bring these new devices to shelves, so we’ll have to wait and see if they work as well as they sound.

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