Tenacity Electool Co,.Ltd (Massa TOOLS) is a professional manufacturer of Screwdriver Bits, hex key wrench, and Accessories for power /pneumatic tools for more than 20 years in China. The products have been selling worldwide and have earned a stellar reputation in the screwdriver and bit fields. 上海東耐電子工具有限公司(MASSA工具)是一家專業生產螺絲批頭,六角扳手的公司,在中國有20多年制作電動工具氣動工具配件的經驗。該產品并在一些螺絲刀**域已**世界各地,并贏得了一流的口碑。