A Hahn Hi-Boy H-300 self-propelled sprayer

A Hahn Hi-Boy is a specialized, high-clearance type of farm crop chemical applicator designed to operate in high crops without damaging them. The largest producer of hi-boys is Hagie Manufacturing Company of Clarion, Iowa, United States. The most common uses of Hi-Boy are for detasseling, spraying herbicides, and applying glyphosate directly to weeds growing above crop height with a wick or wiper.

The Hahn Hi-Boy was invented by Lloyd Hahn in Evansville in an undisclosed time in the 1940s