Used to remove heavy rust and contaminants fast. Multiple needle design means removal process follows surface contours. Air Powered (requires 6cfm). Electric versions are also available. Available with 1/16″ (2mm), 1/8″ (3mm), or 3/16″ (4mm) Needles. Vacuum Shroud means gun is suitable for hazardous material removal. This requires a connection to a separate vacuum source. Ergonomic pistol grip design.