The Snow Lake Zone is one of the permitted camping areas in the Enchantments. Permits here are very hard to get via the lottery (but easier to get than a permit for the Core Zone). You can also camp in the Snow Zone if you have a Core permit.
Snow Lakes is amazing. It's about 8 miles backpacking in from the Snow Lake Trailhead. It's at elevation, but not as cold as the Core Zone.
There is a backcountry toilet at Snow Lake (no walls, just a toilet), but no other amenities. There is water everywhere in the Enchantments, if you have a filter, you're never more than steps away from an alpine fresh water bottle refill.
I used my 15 degree sleeping bag end of July (I'm a cold sleeper and the temps were about 30)
There are no fires allowed.
The best camping place we found was a little spit at the far end of the lake (almost all the way to the end that is closest to the core zone)