The mandrels are precision-made from high-grade stainless steel and are designed to fit both NT-3000 and NT-1000 neck turning tools, as well as most older models.
Expander mandrels are sized 0.001" larger than turning mandrels to prepare the case for a perfect fit, enhancing the precision and ease of the neck turning process.
These mandrels can also be used to increase the neck size of cases to the next caliber with the NT-EXP Expander Body.