Compatible with all for rotary tools and flex shaft. But except discontinued Models 1, 2, and Series 1 or earlier of discontinued Models 260, 270 and 280. Most of the collets used in the market are made of aluminum alloy. This material is soft and easy to wear and tear, so we use a better quality brass material. For plastic nuts, they break during use, and the all-metal material solves this quality problem very well. This replacement brass collet provides a big improvement in and holds these tiny bits far more securely and in better alignment with the rotation of the tool, under high-speed rotation, it not only maintains stability but also improves work efficiency. The package contains: 8pcs brass 4485 collet (0.8mm, 1.2mm, 1.5mm, 1.8mm, 2.0mm, 2.4mm, 3.0mm, 3.2mm) and 2pcs metal change collet nuts., Weight: 0.04850169764 Pounds, Manufacturer: Aisuoka