U.S. Pat. No. 190,459

A 3D model of U.S. Pat. No. 190,459 -- cutting edge 1877 screwdriver handle technology from the original database of things--the U.S. PTO.!

"To all whom it may concern:
Be it known that I, HENRY WILKINSON, of Collinsville, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Screw-Driver Handles..."

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