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Douglas D. Fletcher
Woodbury, MN
US
3 patents
3 Patents
US11617980
2023
Air Filter Condition Sensing
3M Innovative Properties Company
0 cites
US11607635
2023
Air Filter Condition Sensing
3M Innovative Properties Company
0 cites
USD0978443
2023
Hearing Protector
3M Innovative Properties Company
0 cites