The FSLD-840-04 from Frankfurt Laser Company is a Superluminescent Diode with Wavelength 830 to 850 nm, Output Power 3 to 4 mW, Bandwidth (FWHM) 45 to 50 nm(Spectral Width), Forward Voltage 2.8 V, Forward Current 180 to 220 mA. More details for FSLD-840-04 can be seen below.