The Dremel 4000 variable speed rotary tool offers the highest performance and most versatility of all Dremel rotary tools. The increased strength of its motor plus electronic feedback circuitry enables consistent performance at all speed levels. Dremel 4000 can use all existing Dremel accessories and attachments plus high-performance attachments to complete the widest range of projects. A slim, ergonomic body provides a 360-degree grip zone for comfort and control in any grip position. High-performance motor for maximum performance at all speeds. Variable speed provides maximum control and precision. Separate on/off switch and speed control dial for the perfect speed every time. Quick collet lock for fast accessory changes. Cool-running ball bearing construction for smooth and quiet operation. Replaceable motor brushes extend tool life.