N120 port system — adds 20mm of effective length
The Nauticam N120 Extension Ring 20 with Lock is part of the N120 port system, adding 20mm of effective length to an N120 port setup so the lens sits at the correct distance behind its port. It uses a removable bayonet mount with a secure locking design, and stacks with the 21110 N120 Extension Ring 10 to fine-tune the overall length for a given lens-and-port combination.
Consider this extension ring if you:
- Need 20mm of extra length to set the correct lens-to-port spacing on an N120 housing
- Want a secure locking fit with a removable bayonet mount
- Want to combine it with the Extension Ring 10 (21110) to dial in an exact length
At a Glance
| Port system | N120 (full-frame DSLR & mirrorless) |
| Type | Extension ring (with lock) |
| Effective length | 20 mm |
| Dimensions | Ø132 × 34 mm |
| Depth rating | 150 m |
| Weight | 0.20 kg |
| Port opening diameter | 98 mm |
| Body material | Anodized aluminium alloy |
| Spare O-ring | 90140 (#90140) |
Compatibility
The Extension Ring 20 features a removable bayonet mount and is compatible with the 21110 N120 Extension Ring 10, so the two can be combined to set length precisely. Exact port, extension-ring and zoom-gear combinations vary by camera and lens — confirm this extension against the Nauticam N120 port chart for your specific lens before ordering.
Related N120 extension rings (with lock)
- 21125 N120 Extension Ring 25 with lock
- 21130 Extension Ring 30 with lock
- 21135 Extension Ring 35 with lock
- 21140 Extension Ring 40 with lock
- 21150 Extension Ring 50 with lock
- 21155 Extension Ring 55 with lock
- 21160 Extension Ring 60 with lock
- 21170 Extension Ring 70 with lock
- 21180 Extension Ring 80 with lock
Resources
- N120 Extension Ring 20 — PDF Manual
- N120 port charts (choose the correct extension + port for your lens): Canon EF, Canon RF, Canon RF II (C50 / R6III), Nikon F, Nikon Z7 / Z7II / Z8 / Z9, Nikon Z6III / Z5II, Nikon ZR, Panasonic L, Fujifilm GF, Cinema (Canon)
