Higonokami (肥後守) knives are a form of traditional Japanese pocket knife that dates back to 1896. The blade of these friction folding knives can be safely kept in the 'open' position by applying thumb pressure to the Chikiri ('Tail' lever) that is integrated in to the blade.
The handle of traditional Higonokami knives was made from stamped metal sheet, typically brass, but some contemporary knives feature beautiful figured wood or hi-tech carbon fiber.