1", Crimped End Wire Brush With Carbon, Highly Specified Wire Grades Are Constructed With Internal Holding Plate To Ensure Consistency & Safety Constructed For Even Balance Which Provides Smooth Performance, Wire Is 100% Inspected To Meet Demanding Quality Specifications, 1" x 1/4" Stem, 0.02 Wire Gauge, 1/4" Stem Arbor Size, Maximum Speed Is 20,000 Rpm, Knotted Wire Is For Heavy Material Removal, Crimped Wire Provides Flexibility For Light Removal Of Rust & Paint & General Cleaning.