The impact screwdriver pattented by Vessel.
 
Every time the Phillips screwdriver you have been using for the last 30 years cams-out and ruins a perfectly good screw could have been avoided by using the proper tool, a JIS screwdriver.
The screw on our bikes are made with the Japan Industrial Standard (JIS) which in this case tries to avoid cam-out when a lot of torque is applied, the opposite of the Phillips standard.
 
For a very informative article on the subject of screw standards go to Instructable. For those who prefer to watch videos MC garage and a few others cover the subject.
 
There are many Japanese tool brands and even a few specialized in screwdrivers (VESSEL, ANEX, SUNFLAG,...). Curiously outside of Japan it was difficult to find JIS screwdrivers adapted for Japanese motorcycles.
 
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