kznanzn 4pcs stainless steel shaft collars bore 3/8 inch out diameter 3/4" with screw fixed kznanzn (1)this set screw shaft collar is made of solid 304 stainless steel, the setscrew-type shaft collar has improved holding power when the shaft material is softer than the setscrew material which supporting low axial loads and simple positioning. good axial and radial support performance. <br><br>(2)shaft collars are ring-shaped devices primarily used to secure components onto shafts. they also serve as locators, mechanical stops, and spacers between other components. in setscrew collars, screws are tightened through the collar until they press directly against the shaft, and in clamping collars, screws are tightened to uniformly compress the collar around the shaft without impinging or marring it. <br><br>(3)suitable for nearly all types of machinery and industry, such as drive shafts, agricultural implements, medical equipment, gearbox assemblies, motor bases, machine tools, and paper and steel mill equipment, the automotive industry, the manufacturing industry, the hobby craft industry.