4300/5-40 Dremel 5 Attachments, 40 Accessories High Performance Rotary Tool Kit with LED Light features a high performance motor providing maximum power and performance at all speeds with the variable speed ranging from 5,000RPM to 35,000RPM and electronic feedback that auto adjusts power and speed for the most consistent performance. 4300/5-40 Dremel 5 Attachments, 40 Accessories High Performance Rotary Tool Kit with LED Light features an Universal 3-jaw chuck which allows for th use of all Dremel accessory shank sizes making it compatible with the entire Dremel high-quality line of accessories. 4300/5-40 Dremel 5 Attachments, 40 Accessories High Performance Rotary Tool Kit with LED Light features a pivot light which rotates to illuminate projects in difficult to reach spaces and the innovated airflow system has a ventilation mechanism which helps prevent heat build-up for better operation and has replaceable motor brushes to help extend tool life.