Below are the features are posted by Pentil® regarding this pen.
- Archival roller system with smooth, pigmented ink delivered through the long-lasting ball delivery system
- Acid-free, archival safe ink is ideal for sketching, drawing, manga art and so much more
- The tungsten carbide roller tip guarantees a consistent line from the first to last drop of ink
- Pigmented ink is light-fast, bleed-proof, water-resistant and fade-resistant
- Available in four line sizes: 0.3mm (extra-fine), 0.4mm (fine), 0.5mm (medium), and 0.6mm (bold).
Since the ink is archival and acid free, I decided to try this pen. I purchased all the available line sizes. I particularly used the 05 nib on some parts of this drawing. Pentil states that this pen is a tungsten carbide roller tip, so I had high expectations. I have a Rapidograph tungsten carbide jewel tip that now costs around $50.00. The Pentil Hybrid Technica pen is a plastic, disposable pen that retails around $3.00 per pen. Pentil also sells the refills for $1.29 but the line sizes you need may not be readily available.

I specifically used the 05 mm nib. Pentil does not specify if the line width or point sizes correspond to the point/pica system of typographical measure. If you are into technical drawings and technical pens, you should read on this further and familiarize yourself with ISO128 standards. For this purpose however, I will use subjective and lay terms.
For my drawings, I normally use the finest nib of a pen brand for the details. I decided to try the pen on the background. Depending on the area, I either use stippling or miniature squiggling marks. I was alarmed because the pen had a little sticker that stated "Avoid tapping base." Hmmmmnnn. What is stippling? It is a continuous tapping motion. Granted I am not tapping the pen the way irritating officemates do during the meetings, stippling is still tapping. Okay, so I used miniature squiggles. I used the pen for squiggling and for gross stippling.

Will I buy these pens again? My answer is yes. The ink is acid-free, archival quality and it is INTENSE! Notice the output of the ink compared to the other pen brands I mentioned above. So, for intense backgrounds I will use this pen. It is comparable to Pitt pens which use India ink. Should I trust the pen manufacturer's labels? I will also find out if they have blue ink, so I can use it as a signature pen.
You know, there is a drawing I made when I was a teenager using a Rapidograph pen with India ink. It hangs on the wall of a brightly lit schoolroom in the Philippines. I doubt the glass is sun and fade-proof. It still looks great after all these years. We shall see 35 years from now if this drawing will still be intense. I will be in my eighties then.
Thank you for reading.