From Above Sockdolager Rapids

Mile 78.6
Sockdolager Rapids
19' Drop

Sockdolager Rapids is among the most rigorous on the river. It occurs at the mouth of Hance Canyon in Granite Gorge where the V-shaped canyon provides no opportunity to stop and survey the best course. Prepare to ride out a rather rigorous go. Batten down the hatches. Prepare to get wet.
--from "Guidebook To The Colorado River"