UMIDIGI's latest smartwatch, the Uwatch2, boasts a fully metallic unibody, an IP67 rating and a 1.33-inch 240x240 display. The OEM claims that it offers 25 days' worth of standby time and 7 to 10 days of active use. It is sold at US$33.32, although this comes down to $24 with an upcoming promotion.
https://www.notebookcheck.net/UMIDIGI-releases-the-Uwatch2-a-new-full-metal-super-economical-wearable-for-US-33.427033.0.html