The Mitsubishi ML-4402 is an AlGaAs laser diode with a near infrared wavelength around 785nm, in a 9mm package. The output is single transverse mode oscillation. The case common pin is laser diode anode and photodiode cathode.
These are new old stock diodes, individually characterized in envelopes.
Output Power: 3mW typical, 5mW maximum
Wavelength: 785nm typical, +/- 10nm Infrared
Operating Voltage: 1.8 Volts typical
Threshold Current: 40mA typical
Operating Current: 50mA typical
Monitor Current: .35mA typical
Package: TO-9, 9mm diameter base
Factory spec sheet found HERE
Note: Due to the sensitive nature of laser diodes, there is no warranty or exchanges on these items.