not for TR300
A343 Sousaphone or Tuba – 3rd slide
YEP-211S(2)
OEM Bach TR300H2 trumpet valve repair kit -- 3 springs
TU331BB Holton Tuba Professional
Conn French Horn, 8D Type, Rotors and Bearings Component:Rotor #4 not for TR300Genuine Conn French Horn parts, 8D, 9D, & others, including some Conn trombones. Rotary valve parts. Brand new from Conn Selmer, not aftermarket. Contact me with your model if unsure. Customer verified some of these components do not fit older 1960s Elkhart 6D. Conn Rotary rotor bearings 16502: Rotor #4, 65. 75mm length, 17. 20mm diameter, 35. 80mm barrel length 16503: Rotor #1, 2, & 3, 65. 40 length, 22mm diameter, 35. 80mm barrel length