Product Features Expansion that extends your investment The full value of your investment comes with expansion that extends the life of your PC. The HP ProDesk 400 MT has three bays and three slots - including storage and WLAN M.2 slots, and configurable ports to fit your peripheral needs. Built on a secure foundation Help protect your PC from security threats with ease using the single interface of HP Client Security Manger Gen5. Receive automatic updates through HP BIOSphere Gen5 and help stay protected online with HP Sure Click.