To ease photographers Nikon supplied and is supplying various focus aids. Below a matrix of most known viewfinder accessories.
| code | product | usable with |
| DK-1 | adapter ring | Nikon F, F2, F3 |
| DK-2 | rubber eyecup | Nikon F3HP, F4, F5, D1-series |
| DK-3 | rubber eyecup | Nikon FM, FE, FM2, FE2, FA, F3 |
| DK-4 | rubber eyecup | Nikon F, F2, F3, F3AF |
| DK-5 | eyepiece cap | Nikon EM, FG, FG20, F301, F401, F501, F601, F50 |
| DK-6 | rubber eyecup | Nikon F801, F90 |
| DK-7 | eyepiece adapter | Nikon F100 |
| DK-8 | eyepiece shield | Nikon F80 |
| DK-9 | rubber eyecup | Nikon F80, D40, D50, D60, D70, D80, D100 |
| DK-10 | rubber eyecup | Nikon F60, F70, F80, D70, D100, Pronea |
| DK-11 | rubber eyecup | fake! |
| DK-12 | attachment ring | Nikon D1-series |
| DK-13 | adapter ring for DR4 | Nikon FM/FE-series, F3, F2, F, Nikkormats |
| DK-14 | anti fog eyepiece | Nikon F3, F5, D1-series, D2H, D2X |
| DK-15 | anti fog eyepiece | Nikon F90X, F100, D1-series |
| DK-16 | rubber eyecup | Nikon D40, D60, D80, F65 |
| DK-16A | anti fog eyepiece | Nikon D2H |
| DK-16C | correction lens -5 - +2 | Nikon D2H |
| DK-17 | eyepiece magnifier | Nikon F6, D2-series, D3-series, D4-series, D5, D500, D700, D800-series, D810/A |
| DK-17A | eyepiece adapter (anti-fog) | Nikon F6, D2-series, D3-series, D4-series, D5, D500, D700, D800-series, D810/A |
DK-17C |
correction eyepiece | Nikon D3, D3S, D3X, D700 |
| DK-17F | correction eyepiece fluorine coated | Nikon D850 |
| DK-17M | eyepiece magnifier | Nikon D3, D3S, D3X and later |
| DK18 | eyepiece adapter | DG-2 on Nikon D3-series, D700 |
| DK-19 | rubber eyecup | Nikon D3-series and later |
| DK-20 | rubber eyecup | Nikon D40, D50, D70, D100, D3000 |
| DK-20C | correction lens -5 - +2 | Nikon D90, D3000, D300s, D3100, D5000, D5100, D7000 |
| DK-21 | rubber eyecup | Nikon D90, D200, D7000 |
| DK-21M | eyepiece magnifier | Nikon D100, D200, D300, D70, D90, D7000 |
| DK-22 | eyepiece adapter for DG2 | DG-2 on Nikon D40, D90, D3000, D300S |
| DK-23 | replacement eyecup | Nikon D300 |
| DK-24 | rubber eyecup | Nikon D5000 |
| DK-25 | rubber eyecup | Nikon D3300, D5300, D5500 |
| DK-26 | cap | Nikon Df |
| DK-27 | rubber eyecup | Nikon D5 |
| DK-28 | rubber eyecup | Nikon D7500 |
| DK-29 | rubber eyecup | Nikon Z50 |
| DK-30 | rubber eyecup | Nikon Z6, Z7 |
| DK-31 | rubber eyecup | Nikon D-780 |
| DK-100 | eyepiece shield | Nikonos RS |
| DK-N | adapter for DK-3 or DK-22 | most digital SLR cameras |
| DF-1 | viewer | for Nikkor 5.6/6mm and 5.6/10mm on flash shoe of Nikkormat FT-N (and later), Nikon F, F2 and F3 For Nikkormat FS and FT a special adapter - to raise the viewer - is needed |
| DL-1 | illuminator | for Photomic T/TN/FTN |
| DG-1 | eyepiece magnifier | Nikon F2, Nikkormat-series |
| DG-2 | eyepiece magnifier | Nikon FM/FE-series |
| FE-10 | adapter | for DG-2 and DG-3 on Nikon F50, F401, F601 |
| FE-12 | rubber eyecup | Nikon F301, F401, F501, F601 |
Many thanks for reporting mistakes.