Heinrich Zalzer Concerto model double horn 4RV possibly made by Kruspe

1. Case

2. Valves back view

3. Valves

4. F-side tuning slide

5. With Eb slide for the F-side

6. Leadpipe engraving

7. Leadpipe

8. In the case

9. Body view

10. Bell flare

11. Large bow

12. Bell engraving