I bought a new Shimano FC-M171 crank for a low end hybrid bike mostly because it had a chainline of 47.5 mm. and I didn't want to spend more than the bike was worth for a new crank.

The teeth seem to randomly vary in size, not in any systematic pattern. Some are shorter. Some are longer. Some are pointed. Some are more rectangular.

Is this just really, really crappy made-in-China quality or am I missing something?

See jpeg:

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