PACK - I wanted a pack that was light but could also withstand 6000+ miles. I opted for the 55L because I tend to carry more food and have extra random things like camera gear. Also, the fact that the material is waterproof is a huge bonus for all the wet days on the AT.
SHELTER - The tent is a trekking pole tent. Lighter than a normal tent, on the AT, I mostly sleep in shelters with all the rain and snow, so carrying something light just in case makes sense.
SLEEP SYSTEM - Katabatic 15-degree flex quilt. Starting the AT in Feb means lots of cold nights. My coldest so far has been in the single digits with many nights in the 20s. The quilt is a compromise between warmth and weight and does a fantastic job of keeping me warm. On very cold nights, I'll wear all my layers and have thus far been comfortable through the whole trip!
SLEEP PAD - Neoair x-lite wide sleeping pad. I cut my sleeping pad down to roughly 2/3rds its length. You can do it easily with scissors and then iron it back together for an airtight seal. This saves weight, and I sleep with my pack under my feet.
PUFFY COAT - Enlightened Equipment Torrid Puffy. The choice was a simple one of warmth to weight. The Torrid is one of the lightest puffies available and offers great warmth. I use it mostly at camp or on very cold days hiking.
RAIN SHELL - Enlightened Equipment Visp Rain Jacket. A good rain jacket is essential on any backcountry trip but doubly so on the Appalachian Trail. Again a decision of effectiveness and weight. The jacket hasn't wetted through for me yet and acts as another layer to keep me warm during very cold temps.
SHIRT - Jolly gear triple crown button down. Great durable long sleeve hiking shirt with a sun hoody. It looks really cool, and in the end, that's all that matters!
MID-LAYER - NW Alpine spider grid hoody. This is my mid-layer, and I wear it most days when the temps are in the 30s and 40s. Breathable so you can stay warm without sweating.
SOCKS - Darn Tough and Point6 Merino socks. Not much to say, but good socks are a necessity! Two pairs. Also, Seal Skinz waterproof socks. Being so early in the season, I'm facing flooded trails and snow, and pretty much every day, my shoes are soaked. The socks help provide a barrier to the water and, most importantly, keep my feet warm through icy slush, snow, and cold creek crossings.
SHOES - Altra Lone Peaks and Timps are what I've been wearing for shoes. Trail runners are light and comfortable. The Lone Peaks I wear through more technical terrain like NH. I use Timps for flatter areas like PA, and the extra cushion helps protect the feet from rocks and such on trail.
FANNY PACK - Hyperlite Mountain Gear Versa fanny pack. I wear this around my chest when it's cold for a little extra insulation and around my waist when it's warmer. It's great for storing snacks and my phone and anything else I need quick access to, like spare camera batteries and sunglasses. It saves a ton of time to not have to take off my pack to access those things throughout the day.
STUFF SACKS - Hyperlite Mountain Gear in various sizes. These I use for carrying food and organizing the rest of my gear so that packing and unpacking is more efficient while also protecting sensitive items like electronics from any rain that makes it inside the pack.
POWER - Anker 20k PD battery. This keeps my phone, and all other electronics charged, and with the PD USBC, I can get a full charge off a 45W wall charger in 6.5 hours–important for those days when you need to move quickly through a town. 1-2hrs will give enough charge for another 3-4 days.
CAMERA - Sony A6300 with Sigma 18-55 Lens. Extra weight that is not strictly necessary but capturing the beauty of the trail is absolutely worth it to me. I attach it to my pack using a peak design capture pro so that it's easily accessible and put an HMG Stuff Sack over it during light rain/snow to protect it.
COMMUNICATOR - Garmin inReach Mini. I use this to track my hike, and I can also text with it and call S&R in an emergency.
From this list, I've since ditched the pillow and stove.
With many more miles to cover, this list will continue to evolve. Stay tuned for updates as I continue to make my way through a Calendar Year Triple Crown.