APC Smart-UPS XL protects your data by supplying reliable, network-grade power with scalable run-time in tower and rack mount form factors. With optional, matching battery packs, run-time can be easily extended and optimized for the application. APC understands long run-time requirements, so Smart-UPS XLs can be configured with up to 10 additional battery packs - for run-times exceeding 24 hours, if necessary.