The letter "C" in [C]ycle Marker Pen stands for Carbon and Cycle. With a patented additive, 90% of the pen is biodegradable, promoting efficient carbon recycling in nature.

The pen's unique double-open cap design enhances convenience and sustainability. It can be easily pulled off for immediate writing or twisted off to add ink without staining your hands. This feature increases reuse and recycling potential, balancing product durability with environmental protection.