Order our Verdi Pitch Tuning Forks online and return to the scientific tuning of the classical composers - C=256Hz, A=432 Hz, C=512 Hz. Our brand new, aluminum, 2 pronged naturally vibrating, American made tuning forks will keep you in tune. These musical forks are also used for medical research, healing, classrooms and more. Art and science, like politics, must be complementary, and not arbitrary. Having an arbitrary pitch of A=440 is like having a ond foot long ruler at 13 inches, because it "looks" or "feels" better! For the human singing voice, and for many ancient instruments, including the very old violins, and keyboards, the modern high tuning does not take physical laws into account and is therefore disastrous. Register breaks and poetic coloration occur will be at odds with the classical composers' original intent. Order one fork or all 3 as a set.