The sportswear brand On has hired a fellow Zuricher company, Verity, to refine its third-party warehousing. The method: a fleet of autonomous drones that fly around scanning and rescanning the inventory.

By Verity’s reckoning, the average warehouse turns over its stock eight times per year and, between lost pallets and lost labels, generates errors on 5 to 15 percent of the items. Finding and remedying such problems takes a lot of manpower and tends to wear down a human staff. Drones can do the job fast, accurately and constantly, with no need to climb ladders or write things down. According to Verity’s co-founder and CEO, Raffaello D’Andrea, the drones can achieve “better than 99.99% reliability rates.”

The system is already in use at an On warehouse in the US and is apparently reducing warehouse-related emissions of CO2. Verity says that its clients tend to reduce these emissions by 1,000 tons per warehouse per year. The company has drone fleets in operation at about 80 warehouses worldwide.