#40 Roller Chain
40B24H-3/4" Type B Finish Bore Sprocket for #40 Roller Chain 24 Tooth
What stands out about this ratchet socket wrench is the tight grip on sockets.
40B24H-5/8" Type B Finish Bore Sprocket with KW-SS
A nice touch on the Oil Equipment Mfg 4171 is the rubber feet that reduce vibration during operation.