Zyxel SFP-SX-D. Maximum data transfer rate: 1000 Mbit/s, Maximum transfer distance: 550 m, Wavelength: 850 nm. Form factor: Plug-in, Safety: Class 1 Laser, CSA, TUV, 21 CFR 1040.10 & 1040.11. Width: 56 mm, Depth: 13.4 mm, Height: 12.5 mm. Dimensions (WxDxH): 56 x 13.4 x 12.46 mm