Important Remind (1):7 Inch dust shroud fits:Make sure your grinder’s or polisher’s collar is between 38 and 62 MM.If it is less than 40 or more than 73 MM, it does not fit the dust shroud.Dust Shroud’s removable front edge of shroud make it possible to grind close to wall or edge. This package carries (a)-(c):(a) 4 Pieces of the 7″ Diamond Double Row Grinding cup wheel for stone concrete granite travertine surface grinding / smoothing (non-threaded. inner hole diameter 7/8″-5/8″). (b) 1 Set of the Lock ring nut and wrench (it fits 5/8″-11 thread spindle grinder / polisher. The cup wheel can connect to your grinder / polisher directly with it). (c) 1 Piece of the 7″ Dust Shroud ( removable front edge of shroud make it possible to grind close to wall or edge). Make sure your grinder’s or polisher’s collar is between 40 and 73 MM.If it is less than 40 or more than 73 MM, it does not fit the dust shroud. Description of Dust Shroud:- compatible with most hand grinders including Makita, Bosch, Secco, Hadin, Dewalt (Please confirm with us if you are not sure whether it fits your grinder/polisher). – It captures up to 99.4% of airborne particles for outstanding dust control that preserves air quality and protects the user from harmful working environment. – It fits all 6″ or up to 9″ grinder/polisher. – The removable front edge of shroud make it possible to grind close to wall or edge.