Title:
Expanding drill
United States Patent 1357689
Inventors:
Willis, Clark
Publication Date:
11/02/1920
Export Citation:
Click for automatic bibliography generation
Assignee:
Charles, Clark D.
Primary Class:
175/263
Other Classes:
175/421
International Classes:
B23B51/00; E21B10/32; B23B51/00; E21B10/26
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