The GRC T4-NYBW typewriter ribbon, often called the New Universal Typewriter Ribbon Spool, is described by the manufacturer as a flexible option for various classic typewriters. It features black nylon cloth for steady ink quality alongside a white correction tape, which makes it handy for replacing vintage models like the NU-KOTE BW277, PORELON BW277, Sears 53770, and Smith Corona SC-20BW-SCM.

From what we've gathered, the ink quality of this ribbon gets mixed reviews. Some people say the ink is vibrant and creates clear, sharp text suitable for different writing needs. The nylon material seems to help with smooth ink transfer, keeping the text bold through multiple uses. One person mentioned it worked perfectly, saying, "Exactly what I needed and it fit well in my Sears 'The Scholar' typewriter," which shows it can perform well with certain models.

But a word of caution: while this ribbon fits many models, it's not a perfect fit for every typewriter out there. A few folks mentioned running into compatibility issues, especially with models like the Smith Corona Electra. Someone pointed out, "Ribbon doesn’t fit in my Smith Corona Electra typewriter," so it's crucial to double-check your machine’s specs against the ribbon's compatibility list.

Feedback on the correction tape is also somewhat varied. Although it's nice to be able to correct mistakes right on the page, some users mentioned having trouble with the tape. Reports of flaking or dried ink on the correction tape popped up, like when one person noticed the "whiteout flaked off," which can be troublesome if you rely on the correction feature a lot.

All in all, the GRC T4-NYBW usually delivers decent ink quality if your typewriter is on its compatibility list. It can help maintain clear and vibrant text, but just make sure to verify your typewriter model before buying, and be aware of potential quirks with the correction tape to get the best results.