Decrypt the drill bit code. To decrypt the drill bit code: Open the decoding tab of the drill bit code by selecting "Decoding Drill Bit Code" from the menu on the left. Select a drill bit type (rock cutting tool group) from the list. In each of the four cells (located below the selection item, select the type of drill bit), select the required symbol for the drill bit code. The result of the decryption will be automatically displayed under the items for selecting the type of drill bit and cipher