U.S. Pat. No. 190,459

SummaryA 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..." More here!