Tubing bears the patent date of July 12, 1910. Eb bass shown in the Oliver Ditson Guidebook from the 1920s. Perfectone Made by J.W. York and Sons Grand Rapids, Mich. Bore is .463. There are two tuning slides on the leadpipe.
Instrument is unique design with first tuning slide tightly wrapped along valve section.
J.W. York and Sons valve trombone Professional model instrument according to contact. The mouthpiece with this instrument is stamped York and Sons. The instrument bears the patent date of July 12, 1910. Bb cornet Instrument is brushed silver with gold wash in the bell. Instrument came with extra slides.