3020 Set of 8 tuning forks

The items are made of chrome steel, with different length and section of 4.0×7.5 mm.
Hz frequencies : 256(DO) – 288 (RE) – 320 (MI) – 341,3 (FA) -384 (SOL) – 426,6 (LA) – 480 (SI) – 512 (DO) Hz. With case and hammer.
Suitable for demonstrating the tones-frequencies relationship, and for tuning music instruments.