This catalog introduces ANLET's BO 50-200A series of three-lobe Roots blowers, engineered to support carbon neutrality initiatives. As positive displacement machines, these blowers deliver consistent performance for diverse industrial applications. The BO series encompasses models from BO 50A to BO 200A, offering a broad spectrum of performance capabilities. Detailed performance tables illustrate standard suction air volumes (e.g., from approximately 1.66 m³/min at 1150 RPM for BO 50A to 55.6 m³/min at 1500 RPM for BO 200A) and corresponding required power (kW) across discharge pressures ranging from 10kPa to 80kPa. It is crucial to note that for pressures exceeding 60kPa, high-pressure specifications (BOOOH type) are mandatory, as standard models are not designed for such conditions. Technically, these blowers operate volumetrically, meaning air volume and output are directly proportional to rotational speed, while torque characteristics remain constant. For precise control using an inverter, a recommended variable speed range of 60-30Hz is suggested. Users must exercise caution regarding potential resonance between the blower and motor, particularly when anti-vibration mounts are employed, to prevent abnormal noise and vibration. Standard accessories include an intake silencer with filter, pressure gauge, base, belt cover, safety valve, V-pulley, V-belt, and anchor bolts. Optional accessories, such as discharge silencers (ADS and AGOS types) and flexible joints (rubber AFD-N type and stainless steel AFR type), are available to customize installations. Comprehensive outline drawings and dimensions are provided for each model, including BO-H types which feature modified base sizes.