The district of Soya, where the village of Sarufutsu in Hokkaido is located and is Japan’s largest scallop catch, generates 40,000 tons of shells annually as fishery product waste during the scallop processing process. In 2021, the export of these shells to other countries for reuse purposes would be discontinued, posing a social problem for the region in the form of environmental impact caused by storing shells on land and finding a place for them to be deposited. In the course of studying measures to solve this problem, we learned that the main constituent of scallop shells is calcium carbonate, and began development based on the idea that scallop shells could be reused to make a new material. By recognizing that scallop shells are also an important resource that supports the village, efforts to recycle scallop shells were initiated. The new material created as a result of these efforts is Shellstic. Inspired by the original role of the shells as a protection against foreign enemies, HOTAMET was born as a helmet using the Shellstic to protect the scallop fishermen who undertake the potentially dangerous task of scallop fishing. In recent years, the risk of natural disasters such as large earthquakes and extreme weather has increased, and this helmet is intended to be used not only by scallop fishermen and residents of Sarufutsu Village, but also as a helmet to protect oneself from natural disasters, regardless of occupation or region.