Built to work in Dewalt Drill but can work in any pressure lock drill. Add your bit to the end for custom applications (see my mixer model for ability). The bit is set to 7.2x6.2mm which is the exact scale of my drill. The opening can range anywhere from 6-6.2mm. It took me about 4 prints to get it right (feeling the lock click). Creality G-code set for High-Quality print using Hyper PLA. Go nuts!