Ko-soto-gake is a throw to the rear. Although it looks similar to Kosoto-gari there is a big difference. This waza is a gake. Hook the leg and drive backwards, rather than sweeping.
To see other foot-sweeps visit the judo throws page.
Go to page 40 of Fifty Throws and Holds to learn more about this throw. This book contains the entire Gokyo! That is the entire judo syllabus. Buy the book here.
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