Airsoft guns (also known as Soft Air Guns) are spring, electric, or gas powere air guns that fire small spherical plastic pellets of either 6 mm or 8 mm diameter (0.24 or 0.32 inches), although spring-operated "air guns" may be disputed as air guns altogether. Very cheap airsoft guns are normally underpowered and unsuitable for match play, but some Chinese manufacturers such as Jing Gong, Echo 1, A&K and BOYI/ D BOYS are now producing match-quality AEG's for under $100. The more expensive models by manufacturers such as Tokyo Marui, Classic Army, and G&G are preferred by professional players due to their reliability and accuracy.