As noted by AppleInsider, new seasonal bands for the Apple Watch are available in a range of colors, including the Nike Sport Band.
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Previously, you could only get the Nike band if you bought an Apple Watch Nike + model. The sport bands cost $49 and come in black/volt, anthracite/black, and pure platinum/white.
Woven nylon bands ($49) are also available in six new colors. And the the $149 classic leather design has been updated with new options.