The Mekko AD-303 and AD-305 series represent the high-capacity storage solutions for large-scale electronics manufacturing, offering a generous 750-litre capacity within a space-efficient floor-standing footprint. The AD-303 features a traditional three-door front configuration, while the AD-305 offers unique five-door access (three on one side, two on the opposite) to facilitate “pass-through” workflows or specialized inventory management. Both models are powered by the MTX-Flow active desiccant system, which provides a continuous, closed-loop humidity control environment at 1-3% RH without the use of consumables like nitrogen or compressed air. These cabinets can accommodate up to 30 removable sliding shelves, allowing for the storage of vast quantities of moisture-sensitive devices (MSDs) in full compliance with J-STD-033C. The integrated real-time computer read-out and precise $\pm1\%$ RH humidity meter ensure that quality managers have total visibility over storage conditions, preventing delamination and micro-cracking defects in high-reliability aerospace, medical, and automotive electronics.