The wolf tone mute in this set are adjustable, allowing you to fine-tune your cello's sound to your preference. They are easy to install and compatible with cellos. The included mute is for practicing in quieter environments, reducing the volume without compromising the quality of your sound. Features -Color:Assorted Color -Material:Metal, Rubber -Size:3.50X3.50X1.30cm/1.38X1.38X0.51in -Size:2.20X1.30X0.80cm/0.86X0.51X0.31in -Adjust setup: the wolf tone mute can be used individually or together, flexibility to suit various playing styles -durable craftsmanship: made with durable materials, ensuring performance and reliable sound control for cellists -Effortless adjustment: adjustable design allows musicians to fine-tune their cello’s tone with ease, enhancing overall sound quality -For cellists: specifically tailored for cello players, this set addresses common tonal challenges and improves musical expression -Ideal for all occasions: suitable for practice, rehearsals, and live performances, providing consistent sound control in any setting Package list: 2 x cello wolf tone mute 1 x rubber mute