Nomad Motorcycle Tank Bag – 4L Heavy Duty Black Gas Tank Bag with Touchscreen Phone Window, Magnetic Universal Fuel Tank Pouch for Cruiser, Sportbike, Touring & Street Bikes

Nice ride choice! I've got a 2021 z400 abs as well. If you need some options for other accessories options, I threw together this post a while ago. The tank grip stickers did fall off but I redid the backing glue with new 3m tape and they're good as gold now. https://www.reddit.com/r/Ninja400/s/9AnKYJ8flw This bag has been great for me. It's plenty big enough for my phone and other junk, and is magnetic so quick access to the tank for filling. Have had it for shy of 2k miles and it's done well. Tank bag: https://a.co/d/0cEIU5DS If you need a bit additional space for cheap, this tail bag works well and clips right on to the rear seat pad. I usually keep a few water bottles in it when riding. You could probably throw a small ice pack in there as well to keep it cold. https://a.co/d/00HkkPOm