What is the degree of hardness of silicone pen covers on the market today? What Japanese brand uses a double layer of silicone?

Hello! How much hardness is on the market silicone pen case is generally 30-45 degrees or so, silicone hardness are used Shore hardness meter to accurately measure (frequent contact by hand can also be roughly feel out).

Generally Shore A30, 40, 50, 60, 70, the hardest can do 90, 95 or more.