Kiyotsuna and Ikkaku Donryu are both produced by Shimizu Cutlery, which is based in Seki. Seki is historically known for quality katana swords, and today it produces some of the best kitchen knives in the world. Shimizu Cutlery combines traditional methods with modern technology to create and innovate cutlery suitable for its customers. They offer a wide variety of affordable knives for the home to professional kitchen.
Ikkaku literally means "one corner" and this name was chosen for this brand because the president's mission is to become the best in one corner (or one aspect) of the cutlery world.