Title:
Manhole cover
United States Patent 1825726


Inventors:
Gredell, Otto N.
Application Number:
US39541729A
Publication Date:
10/06/1931
Filing Date:
09/26/1929
Assignee:
STANDARD STEEL WORKS
Primary Class:
Other Classes:
70/164, 220/315, 292/259R
International Classes:
F16J13/04
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