Ken Onion (born January 16, 1963) is an American custom knifemaker based in Kaneohe, Hawaii, United States who invented the "SpeedSafe" assisted opening mechanism for Kershaw Knives.

[5] [dubious – discuss] In 1989, Ken's wife, Noel, made arrangements through a friend for Onion to meet custom knife maker Stanley Fujisaka.

[5][6] This contract led to Kershaw expanding its factory and number of employees to accommodate the demand for these knives.

In 2010 Onion parted ways with Kershaw Knives to start his own production company and to collaborate with Columbia River Knife and Tool on several designs.

[8] An article in Blade Magazine asserts that celebrities, such as Steven Seagal, Steven Tyler, Nicolas Cage, Kid Rock, Pamela Anderson, Wayne Newton, Emily Ahern, Stephen Lefebvre, Wayne LaPierre, Brett Morss, and Ziggy Marley collect custom knives made by Onion.