A Single-Row Four-Point Contact Ball Slewing Ring works like a big turntable for cranes and excavators. It has one raceway where four balls touch both inner and outer rings, so it can take side loads, thrust loads and tilting forces at once. We fit it between the superstructure and the base, letting heavy parts spin with low friction. Made of heat-treated steel, it lasts through tough jobs. Think of it as the smooth spinner that keeps your heavy gear turning, no noise.