Luckily, the SWR10 is meant to be worn all day, and Sony rates battery life up to five days, so you probably only have to take it off once or twice a week. It felt secure once in place, but I had a hard time getting it on in under a minute. There's a dual-prong silver toggle built on the bottom edge of the strap, but no matter how many times I wore it, securing the closure proved to be an exercise in frustration. Getting the strap onto my wrist was also an issue. I can't speak for any other color, but it was definitely visible on the black strap. The default strap is made of a rubbery material with a lightly textured pattern which picks up stray bits of lint and debris. The SWR10 ships with two black straps, but Sony plans to offer a number of replacement packs with different colors later this month. The strap is the same width no matter which size you choose, so it doesn't make any difference from a style perspective. I found the smaller strap to be a reasonable fit on my somewhat large wrist, so I imagine it will also work for most other users. On the wrist, it looks extremely similar to the Fitbit Flex ($62.99 at Amazon), minus the small display. The strap itself measures roughly 0.65 inches at its widest point, and just over a quarter of an inch deep. The core comes with two different-size straps in which you can wear it, which is where the S martBand aspect comes into play. There isn't really a clear top or bottom, but one of the ends has the model and serial number of the product along with other information, while the reverse features a recessed Sony logo. It isn't meant to be seen, so the design is simple and functional: There's a micro USB port for charging on one end, and a multifunction button and three status lights on the side. It looks a bit like a thumb drive, or even the Fitbit One ($329.95 at Amazon) to a degree. Physically, the core is a small, white piece of plastic that measures roughly 1.5 by 0.6 by 0.3 inches (HWD) and weighs less than an ounce. The band itself is really just a body for what Sony calls the core, which is the brain of the device. Design and FitAt a glance, the SWR10 looks a lot like your standard, nondescript activity tracking band, but that's only half of the story.