Unlike the 2DX batteries, the DX 4DX batteries have four cells. However, they are every bit as reliable and cost-effective as their two-celled counterparts. The 4DX batteries were also designed with high-rate UPS applications in mind. The heavy-duty DataSafe DX 4DX-11B features a calcium flat-plate construction. Its design includes optimal grid, dual lug, and Slide-Lock features. The whole battery is encased in a PVC fire-resistant case. The DataSafe 4DX-11B lasts for up to 20 years and is rated at 100% capacity at initial discharge.