The history of ""airsoft"" originated in Japan during the mid-1970s, mainly because it was illegal to own firearms by private individuals. The first airsoft guns available were spring-powered replicas of firearms that fired 6mm, plastic pellets or BBs. The gun then spread to China, Hong Kong, Korea, Taiwan and the Philippines and became very popular chiefly because of firearm restrictions in these countries. The first airsoft guns were those air driven pellet guns, cap-type guns and spring driven pellet guns. The early Japanese air driven pellet guns were based on semi-automatic pistols. They were spring powered. The plastic pellet was propelled by air when the spring piston was released. In the cap-type guns, powerful an explosive cap was used to make the sound of gunfire and to eject the spent cartridge. In spring driven pellet guns, a spring was used to propel the pellet held between two small locks and released when the gun was fired. Mattel, the famous American toy company had already marketed a product called ""Shootin Shells"" way back in the 1950s. These guns were identical to the spring driven pellet guns and had Stik-M-Caps that explode to emulate the sound of gunfire. In the 1980s, Daisy BB Gun Company manufactured spring gun models called Replisoft and Soft Air shot at each other by opposing players. The popularity of airsoft guns in the United States and Europe began in the mid-1990s. There is continued growing interest in the west. In 2003, Daisy started manufacturing and marketing airsoft guns once again in the United States. ""Powerstrike"" is the brand name used by the company. Other manufacturers are following in Daisy's footsteps and a host of different models have entered the United States airsoft gun market.