Copper hand warmers, also known as "sleeve warmers", "hand smokers" and "fire cages", are palm-warming tools commonly used in the palace and even among the people in the old days. The art of making red copper warmers in the Qing Dynasty was distributed throughout the country. So far, it is rare to find a master who makes red copper warmers by hand. The skill of making red copper warmers by hand is now only passed down by Zheng Feimin in Guanhaiwei. The production process includes proofing drawings, beating the shape of the device, mesh carving, chiseling and trimming, welding, etc. Each process is closely linked. The works mainly include sleeve warmers, incense burners, smoked warmers, hand warmers, foot warmers, etc. The patterns include geometric pattern cake-shaped hand warmers, woven pattern square hand warmers, geometric pattern plum blossom-shaped hand warmers, etc. The production material is high-quality red copper plate, and the tools include wooden hammers, pillars, chisels, drills, files, scrapers, stools, copper welding tools and sandpaper. Information source: Ningbo Cultural Center (Ningbo Exhibition Hall Ningbo Intangible Cultural Heritage Protection Center) (No pictures yet, welcome to provide.) Information source: Ningbo Cultural Center (Ningbo Exhibition Hall Ningbo Intangible Cultural Heritage Protection Center) (No pictures yet, welcome to provide.)