Apple announced two new Apple Watch models at its “Time Flies” online event today: the high-end $399 Series 6 and the more affordable $279 Apple Watch SE, which serves a step up from the $199 Series 3. Both will release this Friday, September 18th, and if you’re interested in buying one of them, you can place a preorder starting today.

The Series 6 comes in a few new colorways and finishes, and it has more power with its S6 processor and an improved always-on display. Apple noted that this Watch is 20 percent faster than the Series 5 Watch, and it has more sensors than previous models. Notably, it can detect the blood oxygen levels in your body. The Apple Watch SE is a more affordable option that looks similar to the Series 6, but it doesn’t have brand-new sensors or features. It’s simply a cheaper option that serves as a more affordable alternative that is more capable than the bottom-rung Series 3.