This Lessmann Knotted Wheel Brush has the following specification:

Wire Type: Steel
Wire Gauge: 0.35
Diameter: 75mm
Width: 12mm
Shank: 6mm
Max Speed: 20,000/rpm

Lessmann Knotted Wheel Brushes are fitted with a 6mm shank. Ideal for removing scale, rust, deburring and roughening.

417.198.11 is an especially narrow brush, ideal for working in narrow places.