It appears to have the following specs:
- Small bore--most likely .508
- Nickel silver outer slide tubes with no oversleeves
- Yellow brass crook
- Yamaha logo and "M2" on the mouthpiece receiver
- Removable screw in leadpipes
- 1
- M2
- M5
got to love the A.I. answer.M2 and M5:
These specific leadpipe models are designed to offer different characteristics. The M2 likely provides a specific response and tone, while the M5 offers a different set of qualities. These differences are achieved through variations in taper (how the leadpipe gradually widens) and the materials used.