1. Focal length: 900mm
2. Material: Optical glass, metal frame, coating
3. Aperture: F8
4. Shooting angle: 5 Degree
5. Filter size: 55mm
6. Weight: 880g
7. Size: 144.5x111mm
8. Filter diameter: 105mm
9. The closest focusing distance: 3.5M
10. Lens structure: 8 elements in 8 groups
11. Lens purpose: turn back the lens
12. Lens type: T2 type mount, plus T2 type adapter ring, suitable for Canon/Sony/Minolta/Nikon/Pentax/Olympus and other SLR cameras; lens multilayer coating
13. Packing list: Fold back lens, with lens bag, front and rear cover, T-ring is M42 port, one adapter ring
