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Japanese stationery brand SEED brings the convenience of a retractable pen to the humble eraser. The Radarknock Blue features a push-button mechanism that keeps the eraser protected inside its barrel and ready to use whenever you need it.
Its distinctive crescent-shaped eraser offers both a fine edge for precise corrections and a wider surface for everyday erasing. The slim 5 mm tip provides excellent control when removing individual letters, numbers, or small details, making it ideal for students, designers, architects, engineers, and anyone who works regularly with pencil.
Designed for long-term use, the SEED Radarknock features a replaceable eraser refill and a convenient clip for attaching it to a notebook, pocket, or pencil case. Compact, practical, and easy to handle, it keeps corrections quick and your workflow uninterrupted.
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I've tried almost all of the pocket fountain pens out there, especially the ones with a #6 nib, and this Quark is my favorite of the bunch.
The material choice in a stone wash finish is perfect for a pocket pen. It provides good texture to grip and handle the pen, which you will be doing a lot because you need to unscrew to uncap and then screw to post... and then again in reverse to put the pen away. But the zing! of the zirconium makes each writing opportunity such a pleasurable experience. You're able to do this quickly as well because of the minimal turns it takes manipulate the cap. The grooved texture of the grip is also excellent. Just enough to give you a good grip but never in your way. I do wish the grip section was about 1mm thicker though.
I have mine fitted with a Pilot #15 nib and eyedroppered. I smile every time I take it out of my pocket... the zing... the reveal of the 14k Pilot nib... the perfectly textured groove section. The whole package just comes together so lovely!
If I had to complain though, my one gripe is that when posted, the cap wiggles ever so slightly. It's very minor, but you do feel it move in your hand when writing from time to time. Also, mine takes about 1.5 rotations to uncap, but the description says 0.6 turns. On the plus side, it can post in 1.5 turns, even though the description says 2 turns. Not sure if this is just a variance in manufacturing.
But overall this is an amazing pen. I have been eyeing it for over a year and now I wish I had gotten it sooner.
