This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
TuningForkHz. Diapasn afinado Hz Tuning fork by John Walker showing note and frequency in hertz picture taken by me and released into the public domain own assumed Flapdragon Tuning forks Taken with Fujifilm DX
Page 2023 Free-images.com. All images are Public Domain