Looking at the pictures of the PCB inside, there are many unpopulated components (possibly two DC power inputs for high/low voltage like CRS112-8P?), and the board is marked “CRS310-8x+S+” so perhaps some “x” other than “G” was planned?
Outdoor version could be useful for powering UBNT Wave APs (now up to 31 stations! - sadly only their own expensive ones, the usual vendor lock-in game again - and still passive 48V PoE in new devices designed in 2023, not 802.3at compatible so “forced on” required - yuck).