The Siemens S55803-Y130-A100 WLAN Stick is a versatile wireless LAN (Wi-Fi) connecting device that improves the functioning of HVAC systems. This small and light WLAN stick, which weighs only 0.68 lbs, is simple to set up and install, offering a smooth wireless connection for a range of HVAC devices. https://www.partshnc.com/s55803-y130-a100-siemens-building-technology-wlan-stick