a bike shop can shorten the chain and put it on .. they do not come pre made to your needed length..

AW3 cogs are made in 1/8" & 3/32".. thickness from 13 to 21 teeth ..
the 16t + are dished/offset, 13-15 are flat.
they are low cost, (interchangeably, Shimano 3 speeds use the same cogs)




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