I’ve ganged together two “Add-A-Circuit” units so I can have separate fuses for each seat heater. This fits into Fuse Slot 7 (which is empty in our manual-transmission Fit) and conveniently wraps around the bottom of the fuse panel. (If it were put anywhere else in the panel, the 2nd fuse would stick out too far and prevent the first Add-A-Circuit from being able to be inserted. Note that this is the only arrangement possible for putting two of these together; If it were flipped around, the circuit wouldn’t complete on the 2nd unit (well, unless you wanted 1 post dangling out of the first unit).