Although not sold as an AVP accessory, the FlipBelt Classic running belt is a very useful accessory to have if you want to keep your AVP powered for many hours straight using a power bank. The FlipBelt is a low profile fanny pack which can be worn under your shirt. It's a tube made of stretchy polyester fabric with multiple slit openings that create four pockets for storing your iPhone, water bottle and other items you would normally have it hold during jogs and other outdoor activities. The FlipBelt has been around for many years. Quite popular with runners.
I found that it also works very well for holding the AVP battery and a USB power bank. I have the AVP battery in the left hip FlipBelt pocket and a 40,000 mAh power bank in the right hip pocket, both connected with a 3 ft USB-C to USB-C cable strung inside the FlipBelt. This setup works great! I'm able to get several hours of power before the AVP battery starts getting low and I need to shut down. Enough to get me through a workday using my AVP as a monitor replacement working remote. I have a 2nd power bank that I can swap out with if I want to keep my AVP powered even longer. I could plug the AVP battery into a power strip with the charger. But I prefer to not have the battery tethered. With the FlipBelt, I don't have to remember to unplug the USB-C charging cable from the battery if I need to get up and walk around the house wearing the AVP. It also keeps my pants pockets free. The FlipBelt Classic sells for $34 on Amazon. You can also find it in stores like Scheels and REI.
https://www.amazon.com/dp/B00JF9DU4U?ref_=cm_sw_r_cp_ud_dp_W2QAHKKY51383G4PG332