A rotary pneumatic actuator is a type of pneumatic actuator that is designed to produce rotary motion. Such actuators are commonly used in various industrial applications, including valves, dampers, and other control mechanisms.

One of the key properties of rotary pneumatic actuators is their ability to provide high torque outputs, making them suitable for heavy-duty applications. They are also known for their precise and reliable operation, which allows for tight control over mechanical systems.

In addition, rotary pneumatic actuators are relatively easy to install and maintain, and they can operate in harsh environments due to their non-electrical operation. They are also cost-effective and energy-efficient, as they use compressed air as their power source. However, their performance can be affected by variations in air pressure, which may require additional control mechanisms to ensure stable operation.