Black Box Fast Ethernet (100-Mbps) Extreme Temperature Switch Module - (4) 100-Mbps Multimode Fiber, 1300nm, 2km, ST - For Data Networking, Optical Network - 4 x ST 100Base-FX Network - Optical Fiber - Multi-mode - Fast Ethernet - 100Base-FX - 100 Mbit/s - 2 km (1.24 Mile) Maximum Distance - Hot-swa