Hardin DC4 4" Vacuum Metal Dust Shroud Cover with 1.75" ID & 1.25" Vacuum Connector Full metal design - sturdy construction | Fast and easy to install & attaches quickly Fits 4" to 5" grinders with 1.75" collar size | Protect workers from harmful dust Excellent dust extraction efficiency catches 99% of airborne dust & harmfull particles Simply install this shroud cover by inserting the grinder collar inside the shroud ID & lock it in using the thumb lever Used with dry polisher to absorb the dust in polishing or grinding work | A 1-1/4" wide Velcro strip for height adjustment and is easy to replace 1.25" Vacuum Port