... different diameter of 2-wings drag bit, 3-wings drag bit, 4-wings drag bit, and 6-wings drag bit.We specialize in supplying ... , seismic prospecting for many years. Our products cover the following:Drag bit are manufactured from forged high quality alloy steel and ... provide highest penetration rate and longest lifespan at roughest condition.Drag bits are designed for medium to hard formation and are ...