tuning forks are made of high quality aluminum alloy, which is more delicate, and lighter. Due to the nature of material, these tuning forks are - and sturdy. With manufacturing and testing standards, the tone is clear; the sound is long and the frequency is precise. tuning forks are widely used in , sound healing, meditation, easing anxiety, yoga and so on. 174 Hz - 963 Hz is perfect for balancing energy centers, enhancing attention, purifying the body and mind, as well as playing with pets and music performance. Buying a tuning fork set can meet your different needs. Tuning forks: 174 Hz, 285 Hz, 396 Hz, 417 Hz, 528 Hz, 639 Hz, 741 Hz, 852 Hz, 963 Hz. Color: Multicolor & wood Material: Wood + aluminum alloy Package Contents: 9 x tuning forks 1 x hammer(Random color and random style, don't accept the specified) 1 x storage bag 1 x wooden stand Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.