Dotco 12-13 Series Gearless Right Angle Grinders, 300 Series Collet feature durable and reliable composite housing. Dotco 12-13 Series Gearless Right Angle Grinders, 300 Series Collet are available in front and rear exhaust models. Dotco 12-13 Series Gearless Right Angle Grinders, 300 Series Collet are suitable for a wide range of finishing and deburring applications.