Lenz 1800 Battery Case

When I'm climbing or skiing, I tend to bring with me my Lenz heated socks.  Unfortunately, when I toss the batteries in my bag, they tend to inadvertently turn on--leaving the battery depleted by the time I need them on the mountain.  To solve for that, I built this simple battery case for the Lenz 1800 battery.  Just place the battery in the case, rubber band it in place, and the battery can no longer inadvertently turn on.  Problem solved!