3 blades API drag bit 1-a large stock 2-good quality&certified by API 3-short ... bit , reamer bit, down hole opener, hole enlarger, drag bit, button bit and drilling equipment for petroleum&gas , ... many major brands including King Dream, CS, Lilin,Drag bits, which is designed for soft formations such ... are easiest to log. Usually 2-wings drag bit, 3-wings drag bit, 4-wings drag bit optional. Shapes can do ...