Opus 88 Koloro Demonstrator
https://gyazo.com/d0918a8906e865d54cd77331878a7e4d
Overview
This is an eyedropper pen with a shut-off valve from Opus 88 in Tiwan. Number 6 steel nib made in Germany and 3.5ml of ink reservior are large enough. The ink flow of this pen is rich but not too much, and the tip is smooth moderately.
After an ink filling using eyedroppers or syringes, you may enjoy writings with it for days or weeks because of the large ink capacity. The translucent barrel makes it easy to see how much ink is remained.
I feel comfortable writing with this pen though it's not light weight, 17g without cap, and not thin, 11mm of section diameter. This is probably because balance of this pen is designed well.
I like cigar shape pens in general, but this pen is an exception. Clearness of flattened cap top and blind cap are really nice.
I usually use it with its shut-off valve closed. When I wrote more than two pages of A4 paper size, I opened the valve and closed it again a couple of minutes after, or at the end of the writing.
Although the pen is named 'Demonstrator' and made of clear resin, I believe this is suitable for use as a 'workhorse pen.' In these six months, I brought it everywhere I went.
https://gyazo.com/ac3b4df0b1608b960c62dff8d239a8d7
Writing sample
https://gyazo.com/f75c2a3f3d8662fd92f33c730011896e
Pen: Opus 88 Koloro Demonstrator, F steel nib
Ink: Pilot Iroshizuku Tsutsuji
Paper: Maruman Mnemosyne 182
Technical specs
Length capped: 148mm
Length uncapped: 137mm
Can not be posted
Diameter capped: 20mm
Diameter uncapped: 15mm
Diamter of section: 11mm
Weight capped: 27g
Weight uncapped: 17g
Ink filling system: Eyedropper
Ink reservoir: more than 3.5ml
Further readings