Standard style (SC) shaft collars use a hardened set screw to penetrate the shaft so as to achieve gripThis penetration yeilds light-duty benefits for applications like thrust collars, abor spacers, sprockets hubs, bearing holders, and shaft protectorsSC collars do not work well when th shaft is harder than set screw or when penetration marks on the shaft are not desirableBlack oxide coating will slightly increase friction and holding power in some applicationsFinish: Zinc Inside Diameter: 1-3/8 Inch Inside Diameter Maximum: 1.3810 Inch Inside Diameter Minimum: 1.3760 Inch Item: Shaft Collar Material: Low Carbon Steel Measurement: Inch Origin: Imported Outside Diameter: 2-1/8 Inch Outside Diameter Maximum: 2.1330 Inch Outside Diameter Minimum: 2.1170 Inch Set Screw Size: 3/8-16 Style: Solid Set Thickness: 3/4 Inch Thickness Maximum: 0.7550 Inch Thickness Minimum: 0.7450 Inch Type: Round Bore 
