REO (Boulder, CO) has released a 594nm (yellow) helium neon (HeNe) laser suitable for cost-sensitive bioinstrumentation and fluorescence excitation applications. The new laser features a perfectly circular beam profile and superior beam quality (M²500:1), with a guaranteed minimum output power of 2 mW. Additionally, these yellow lasers provide low noise output (<1% over the range 30 Hz to 10 MHz) and superior beam stability; long term beam drift is under 0.05 millirad. They are packaged in an industry standard cylindrical head format (1.75 in/ 44.5 mm diameter), and the front plate supports a variety of fiber coupling options. REO offers a choice of OEM or CDRH-compliant power supplies, including time delay, key switch and interlock.