Comparison : Item # 40B9FH, No. 40 - 1/2" Pitch - Finished Bore Sprockets
Item # 40B9FJ, No. 40 - 1/2" Pitch - Finished Bore Sprockets
Item # 40B10FH, No. 40 - 1/2" Pitch - Finished Bore Sprockets
Item # 40B10FJ, No. 40 - 1/2" Pitch - Finished Bore Sprockets
Item # 40B10FL, No. 40 - 1/2" Pitch - Finished Bore Sprockets