Wittner   tuning fork, 4x8 mm., square, nickel plated, d1-293.67 Hz.

Wittner   tuning fork, 4x8 mm., square, nickel plated, e1-329.63 Hz.

Wittner   tuning fork, 4x8 mm., square, nickel plated, f1-349.23 Hz.

Wittner   tuning fork, 4x8 mm., square, nickel plated, g1-392.00 Hz.

Wittner   tuning fork, 4x8 mm., square, nickel plated, g#1-415.30 Hz.

Wittner   tuning fork, 4x8 mm., square, nickel plated, a1-440.00 Hz.

Wittner   tuning fork, 4x8 mm., square, nickel plated, b1-493.88 Hz.

Wittner   tuning fork, 4x8 mm., square, nickel plated, c2-523.25 Hz.