. C-C tubes, with marked holes for each note. With a velvet lined storage container that's included, your tuning can be achieved anytime, anywhere. If you are a singer, correcting your tone, your voice will have more colors and your voice will sound clearer to help you be ready for the show. If you play an instrument, you will be able to sound full and in unison to help nail that next listen or performance in style. Users of this product include, timpani drum players, singers in choir or cappella groups, string instruments such as violin,Ukulele, acoustic guitar, cello, mandolin, banjo, bass, even woodwind and brass instruments such as saxophone, clarinet, trumpet and many more. The perfect gift for the musician in your life, we know you care about your friends and family heres the chance to show them off. Specifications:Material: Metal, PlasticColor: SilverProduct Size: 7*6.5*1cm/2.8*2.6*0.4inItem Weight: 40g / 1.4ozPackage List:1*Pitch CakeNote:Please refer to the measurement. A small measurement error is acceptable within the normal range. There may be a slight color difference due to monitor, camera or other factors, please refer to the physical item.