It’s amazing what a single piece of steel wire can do in the right hands. Just take a look at Tsukushi Pencil Cap by the Tokyo-based Tsukushi Stationery Company.

Not only does it protect pencil tips with its unique spiral design, Tsukushi Pencil Cap enables pencils to clip to notebooks, shirt pockets, and securely into the Tsukushi Pen Case (￥2,700Prices are approximate only and subject to change.
White Rabbit Express service fee and other costs not included.). Choose from gold, silver and amber-tinted stainless steel.

Specifications:
Colors: gold, silver, amber
Cap size (mm): 12 x 17 x 78
Compatible pencil size: φ9 × 160
Material: stainless steel