It makes a battery organizer in two styles. The desk tray is a D-profile bar with a wide flat top; the battery shell is the fun one — a giant AA, C or D replica lying flat with a terminal nub on one end, the stored cell's name embossed on the other, and slots cut into a scooped deck. Every slot uses the cell's published dimensions plus 0.5mm of clearance, across 17 sizes — coin cells from the 6.8mm 377 up to the CR2450, plus AAA through D — so cells drop in snug and lift out without rattling. The battery type you're storing drives everything; the grid recomputes live. Tray style sizes freely (diameter 30–80mm, length 40–120mm); shell style picks a replica preset — AA shell (4× a real AA, 204mm long), C shell or D shell. Slot web is the wall between neighbors: 2mm is sturdy, and dropping toward the 1.2mm floor can squeeze in an extra row. If the count reads zero, that cell genuinely doesn't fit — size up. Print tip: print exactly as exported, flat side down, no supports. Coins stand a quarter of their diameter proud — a CR2032 shows 5mm to grab. The shell's terminal nub is a ~5mm horizontal boss; it bridges fine with a touch of sag underneath, invisible from the desk.