Amazon.com: Compatible with Samsung Galaxy Watch 3 45mm Band - Gear S3 Frontier & Classic Bands/Galaxy Watch 46mm bands, 22mm Soft Silicone Replacement Black Bands Sports Straps Breathable Men and Women :
Samsung Gear S3 Frontier SM-R765 LTE Smartwatch - Black for sale online | eBay
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