Xantrex power octopus, handy!

This Friday’s gizmo is the big kahuna of all the portable power packs that can typically jump start a car (or boat), run 12v gadgets, inflate a tire, and more. Xantrex’s top-of-the-line 400R also includes a 400 watt inverter, an emergency light, and an AM/FM radio with alarm! Inside is a replaceable 20 amp hour AGM battery which seems to have guts (and contributes to a total unit weight of nearly 30 pounds). In my experience, the 400R powered quite a bit of reciprocal sanding, and then smartly alarmed and eventually cut out when the battery went too low, or if I bore down too hard. That’s a digital watt meter showing in the picture (bigger here); when the inverter is turned off, it can show percentage of charge. This thing is obviously designed for emergency backup during hurricanes and the like, but I found it darn useful around my little back field boat yard, and it might have a place on some cruising boats. It’s fairly well made, certainly better than other jump start packs I’ve had. Xantrex’s page on the 400R is here, and a fellow named Jack has written a lengthy and careful review here (he’s right that it takes a long time to recharge, but I thought the radio performed OK, at least a low volume).