Wanting to free from the line constraint, I figured out how to make plain circles from very tight spirals. This bright and colorful series is the first application of this unlocked achievement.

You can offer it and write something nice in the back, you can pin it, blu-tack it, frame it (try in a glass-less frame!), up a wall, on a shelf or on a desk.
Avoid direct sunlight and keep the poster out of humidity.

Paper — 250g/m² (115lb) Clairefontaine PaintOn acid-free paper
Inks — Stabilo fineliners
Format — 15 × 10 cm (5.9 × 3.9 in)