JMJ Diamond Tools provides high quality products to meet our customers needs. We could also help you to find and even design your products to achieve your goals by quality, quantity and services. Thank you for your business and let us win together! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Shaft Extension 1 1/4"-7 Thread 12" Length for Core Drill  Top Quality Shaft Extension for Core Drill Length: 12" Thread: 1 1/4"-7  Package: 10