There are 2 types shown: Smooth vs Serrated (toothed) blade wheels.
Tracing wheels . Smooth & Serrated.
Hemline Tracing Wheel – Smooth or Serrated | Sewing, Dressmaking & Pattern Marki
Milward Eco Dressmaker Tracing Wheel Smooth Serrated Sewing Pattern Marker Aid
Dressmakers Carbons Tracing Paper Squared Paper Tracing Wheels Tool
Pattern Cutting Paper Spot Dot & Cross or Pattern Tracing Paper -Pattern Cutting
