The mineral processing industry usually evolves rather than revolutionizes, but the Horizontal Shaft Impactor (HSI) has revolutionized the crushing process in numerous industries. There are several varieties of HSI, and their similarities are more numerous than their differences. Our Mega-Slam primary impact crushers and Grand-Slam secondary impact crushers are top of the line and low maintenance horizontal shaft impactors. All varieties feature externally fed horizontal rotors with breaker bars, which propel material into a series of apron-mounted breaker plates that crush or pulverize many different types of materials to specified degrees of fineness.