Gas-operated airsoft guns use compressed gas, typically green gas or CO2, to propel plastic BBs. These guns are known for their realistic operation and performance, often featuring blowback mechanisms that simulate the recoil of real firearms. These airsoft guns come in various styles, including pistols and rifles, and are popular among enthusiasts for their accuracy and ease of use. Regular maintenance is essential to ensure optimal performance, as the gas system can be sensitive to temperature and pressure changes.