Characterization testing of monolithic, dual beam visible diode lasers operating at 670 nm (at 20 degree(s)C) is reported for AlGaInP lasers with a 50-micron channel separation. Of particular interest for use in the design of laser scanning systems is an understanding of the characteristic behavior of the thermal droop and thermal crosstalk between channels as heatsink temperature, laser drive current bias, and output power are varied. The thermal droop and thermal crosstalk are both found to decrease as the laser output power is increased. Additionally, the thermal droop and thermal crosstalk increase as the temperature of the heatsink increases. Characterization of the laser wavelength dependence on temperature and output power must also be considered in laser scanning system design. The dual beam laser wavelength was measured to change with temperature 0.17 nm/ degree(s)C. Laser wavelength at a constant laser case temperature was found to increase by 2 nm as the output power was increased from 1 mW to 15 mW.