The note, when perceived as an intentional olfactory signature rather than a mere carrier, presents as remarkably sharp, ethereal, and intensely volatile. It often carries a distinct metallic coolness, bordering on an almost sterile, yet sometimes subtly sweet or plastic-like character. Its initial impact is often effervescent and almost biting, creating a sensation of crisp, clean air or a freshly opened chemical bottle. Projection is typically high and immediate, a piercing clarity that slices through other notes. However, due to its inherent volatility, its longevity as a distinct "note" in its own right is fleeting, quickly dissipating to leave behind an impression of space, modernity, or sometimes a slight, clean hum. It behaves almost exclusively as a top note, serving to introduce a stark, abstract, or highly defined quality.