CRK was established in 1963 in gunma prefecture northern part of Tokyo. Since then, we offer various kinds of rubber materials such as rubber compound, molded rubber, and tapes. One of our main products are graphite based intumescent rubber materials applied for variety of through-penetration wall parts. They expand more than 10 times in case of fire and prevent further passage of flame. We can provide these fire-proof materials at various kinds of tapes, putty, and sponges. Also, we produce water suell rubber sealant tapes made out of chloroprene rubber and water absorption resin, and butyl adhesive tapes applied for water-proof construction materials. In 2007, our fire-proof materials received the Nakagawa award, which represents the most nobel product in gunmma prefecture in the year.Furthermore, our company has received ISO9001:2008 quality management system in 2009 to keep quality of our products high. Our annual sales amount to about 14 million US dollar. Our company has R&D department, so we are able to develop new rubber compounds whatever you want.