These days, there are loads of sub-22in flat bars on the market, but if you're a racer-type you'll probably be looking for something like this.
Oval Concepts' Flat M600 borrows technology from the French aerospace industry in the shape of seamless, triple-butted, heat-treated 7050-T6 aluminium, which apparently is where its low weight and impressive strength come from. Oval Concepts makes a riser version of the Flat M600 as well, and there are graded cutlines down to 500mm, meaning that it's an easy job to make them even narrower if you need to.
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