| US Patent: 1,533,602 
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| Wrench | 
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| USPTO Classifications: |  | 81/99 |  
 
 
 
 
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| Patent Dates: |  
| Applied: | Nov. 21, 1921 |  
| Granted: | Apr. 14, 1925 |  
 
USPTO (New site tip)| Patent Pictures: |  |  |  | Homer A. Mead and Earnest E. Lynch patent April 14, 1925 |  Google Patents
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                        Stan Schulz
 
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| Description: |  | The patent is a self-adjusting hook jaw nut wrench with a spring holding the movable jaw in the closed position. This is the first of several patents for the MASTERENCH. It was followed by 1,634,908, 1,735,257, 1,885,616, and 2,028,406.
The earliest production versions of MASTERRENCH are marked, "MASTER RENCH LYNCHMEAD MFG. CO. - TURLOCK, CAL. - NOV 21, 1921 - FEB 25, 1921 - PATS. PENDING. " |  |