White lacquer and white hardwood saya require slightly more attentive care than darker finishes because discoloration and surface marks are immediately visible. Store the piece away from direct sunlight and UV exposure, which causes lacquer to yellow over time. Maintain relative humidity between 40–60% — too dry and the wood beneath can develop hairline cracks; too damp and the lacquer may lift at seams. Wipe the saya surface with a dry or barely damp microfiber cloth rather than paper towels, which can leave fine scratches. For the blade inside, remove it every three to six months, wipe the steel clean with a soft cloth, and apply a thin coat of choji oil before returning it to the saya. Never store the blade inserted if the saya interior is wet.