Thread set or cap screws into those half threaded holes indicated by the on the below diagram
100E48 Sprocket Dimensions
120A14 sprockets with a stock bore comes with a 1-1/4" inside diameter plain hole and can be easily machine bored to custom sizes
Something else that is notable about this 120B24 sprocket is that it fully meets all ANSI Standards
Bushing Size: 3535
1310 Taper Lock Bushing X 11/16" Bore R1 Thread set or cap screwsThis 1310 taper lock bushing is a high quality, durable, and dependable product that has been precisely manufactured to out last and out perform the competition. 1310 taper lock bushings are used in a wide range of applications including; belt pulleys, sprockets, drum pulleys, drive pulleys, tail pulleys, sheaves, and gears, which are items that we also offer! Additionally this bushing features a 11 16" bore with a standard keyway, for more