The Gear S band (245 x 23.8 x 1 mm) is made from a surprisingly comfy, semi-flexible rubber (Urethane) that stretches around the face and meets up with a metal clasp. I also should emphasize "semi-flexible;" the band is able to bend like rubber but it retains a curled form most of the time. The strap is adjustable up to 10 different sizes and is able to fit a wide variety of beefy wrists, or in my case, tiny baby wrists.
There are also five different proprietary Samsung straps you can choose from: Cobalt Blue, Blue Black, White, Mocha Grey and Supreme Red. However, only black and white are available in the US right now. If you do plan on several switches, the watch body pops out and snaps on to the strap.
The band isn't like the faded leather of the Moto 360, or like many of the first Android Wear watches, but it's also not an uncomfortable plastic either. It's more sporty and seems pretty durable though the rubbery look makes the watch feel less premium.
Luckily the body of the watch makes up for that. As mentioned before, there's a curved screen along with a curved body that cradles your wrist. It's definitely meant for larger wrists but fit mine decently. Though it was hard to see the full face of the watch because it was angled further away - meaning I had to tilt the watch towards my face a bit more than say, the smaller, flat Pebble Steel.
There is one physical home button on the Gear S that sits on the bottom of the watch face. Pressing it takes you to the main watch face. On the left of the watch, you'll find a microphone, placed there for making phone calls and voice activated actions. There's a small speaker on the right for sound output.
On the rear of the watch, you'll find a centralized heart rate monitor and five gold connector pins on the bottom which connect to the charging dock. The back is made of a hard plastic matching the feel of the rubbery strap. It doesn't seem like it would get easily scratched.
The watch is IP67 dust and water-resistant but you can't hop in a pool with it on. It just means you can gently submerge a device in a tank of still tap water up to a depth of one meter at room temperature for about 30 minutes. You can also get a bit of sweat or rain on both the face and strap without lasting damage - which is good news since it's a watch you can't easily hide, bringing us to the next topic.
Again it must be mentioned: the Gear S is a big smartwatch. Coupled with my small wrist, it's positively massive. I can't figure out who it would look "normal" on - maybe someone who's over six feet tall with wrestler sized wrists? It also makes taking coats on and off a pain. The watch tends to get caught on sleeves often. I even had to roll up my longer sleeved shirts because the Gear S wouldn't fit.
I can also feel all of the Gear S's 2.3 ounces when wearing it. Like the LG G Watch R, both could gain a lot by shedding some weight.
The Gear S is probably one of the most uncomfortable watches I've worn. The strap makes turning my wrist inward - or just using my hand to do anything - feel awkward, like I have an ankle bracelet slapped on my arm.
If you're used to big, unwieldy bracelets or analog watches, then it may not be a problem for you. But for someone who doesn't wear jewelry or giant watches daily, it's not very comfortable.