Initials from the names "Hiller-Kelsey-Binger", manufacturers of a first 6-cylinder, 2-stroke, rotary engine with 25 HP. It was the year 1922.

-Another model manufactured under these acronyms was a 6-cylinder with 50 HP.

-They were mounted on the Paterson-Hiller Mono Hydroplane. There was a forecast to build a 60 HP. Without further news.

“HKB, 25 HP”

“HKB, 50 HP”