Twin Peaks Lookout, Custer County, Idaho, Elevation = 10,340 ft.

Located in the Salmon-Challis National Forest

In 1929 there was a 7 by 7ft. cab on the summit which was replaced in 1932 by an L-4 cab. The present structure with an R-6 flat cab on a concrete block base was built in 1964. This lookout is on the National Historic Lookout Register #1002. Photo on August 19, 2018.
An attractive outhouse near the summit.
Reference mark #4 is all that could be found at the summit. Here is the datasheet for Twin Reset: QA0689