HP Procurve Switch 4000m J4121A Managed modular 10/100/Gigabit desktop switches that provide scalable, low-cost switching and all the benefits of HP Proactive Networking. They are ideal for organizations looking for scalable, expandable, low-cost migration to 10/100 switching to the desktop with Gigabit uplinks. The 4000m and 8000m are a simple way to build high-availability networks. The 4000m includes 40 10/100-TX autosensing ports.