Blade sharpener :easy to operate,easy to repair , small size,low weight ,balance speed. Blade sharpenerProduct DescriptionAutomatic straight line blade sharpener.the longth of the working can be adjust as your blade size and longth MODELWorking range(mm)Working angleGrinder speed (r/min)SN-700A0~~7000~~902840SN-21100~~10000~~902840SN-21200~~12000~~902840SN-21300~~14000~~902840