I'd love to get the small (6 Ah) Santi battery for use with my Santi vest. It's very small and compact, but I already have two UWLD batteries for my heated BZ400 and heated Santi vest, so no need at this point. Would you be using heated gloves with it too, because that would limit the battery time. Also, the Santi batteries are either on or off, so no control like an UWLD battery. I had the big Santi one (24 Ah) for a bit, but it was too big for my travel needs because, and I'm sure you know this, but to fly in the US with one of these batteries, it has to be less than 160 Wh.