Gear S3 Frontier vs Galaxy Watch3 - Technically it's a marginally thinner but smaller housing, narrower bezels, and weighs significantly less. It feels thinner than it looks, maybe due to the back
Gear S3 Frontier / Classic Watch Band, Mignova Soft Silicone Replacement Sport Watch Wrist Band Strap for Samsung Gear S3 Frontier / S3 Classic Smart Watch (Military Green) - Walmart.com
Amazon.com: SAMSUNG Gear S3 Classic Smartwatch (Bluetooth), SM-R770NZSAXAR – US Version with Warranty : Clothing, Shoes & Jewelry
Samsung Gear S3 specs, price, release date and everything else you should know