Single edge, deep hole boring bits. The black pieces are centering jigs to help get it all started properly in a large starter hole/bore. Also kept in place to block off the inlet to control cutting oil flow. Check out drilling rifle barrels and that sort of thing. These will drill straight, where the common two flute drill bit we all use will wallow out an oversize hole that will be three sided, especially when starting out. A lot of the time there is a channel or hole down through the bit for high pressure cutting oil to cool the bit and carry out the swarf. Google the topic, you should find lots of examples.