This bi-metal, ice-hardened hole saw has a diameter of one inch or 25 millimetres. It cuts metal fast, and the angled offset slots allow for easy plug removal. It features 4/6 teeth per inch, and a maximum cutting depth of 1-5/8 inch. Fitting pilot drill size 3-1/2 x 1/4 inches. the thread is 5/8"-18, with a shank size of 1/4, 3/8, or 7/16 inch.