Outline* The shown information is the one as of the awarded date and might has been changed.
A Battledore Bolt is a joint hardcore for wooden structure, and work for connecting between wooden beams. The spring, installed with the Sanei Formula Battledore Bolt, is capable of preventing the looseness of a bolt and a nut caused by the dry shrinkage of wooden structure. Additionally, to work efficiently and accurately, the structure of the Sanei Formula Battledore Bolt is designed very simply.
keisuke nakayama, sanei architecture planning