... . All sizes available 2. Large inventory on hand 3. Low cost 4. Can be customized ... bits can be available in open bearing. 4. All come with regular API connections. ... 4 1/2,4 5/8,5 1/2,6 ,6 1/2,6 3/4,7 7/8,8 1/2,8 3/4,9 1/2,9 5/8,9 ... 7/8,10 5/8,12 1/4 ... ,13 3/4,14 3/4 ... ,14 5/8,16,17 1/2 ...