[1] In its final years, it existed as a brand of Apex Tool Group, LLC and manufactured the majority of its tools in the United States, focusing mostly on aerospace, government, and military users.

[3] In 1895, Armstrong introduced a tool holder for lathe cutting bits.

[4] Some Sears Craftsman Professional products lines (such as the former USA made Professional wrench line) were made by the Armstrong Division of Danaher and were virtually the same units, save for the stamping of the different names.

In 1994, Armstrong was acquired by the Danaher Corporation, where it operated as its industrial hand tools division.

In 2017, Apex announced that it would layoff 170 workers at its Sumter, South Carolina plant and cease production of the Armstrong and Allen brands by March 31.