Hello to the 20, or so, people who have jumped into this thread. I asked the OP's question myself. "What's the benefit?", is how I approach these questions. My guess is that the External Torx bolt head is smaller at any given strength. I base my guess on seeing E-TORX fasteners in confined locations on exhaust manifolds. On applications which are not confined at all, like the underside of the ABS unit in my car-a totally smooth bottom-of-a-box, the E-TORX head simply takes less metal to make vs. a hex head. Other reasons relevant to manufacturing economies are things I wouldn't argue. ALSO: To dOOdfOOd and yon yon, It seemed to me that the E-TORX could take a lot of torque and be less likely to slip out of the wrench when I had to change a front wheel bearing. AND: To dparm, Regarding the triple square system; I agree, where is the benefit to that system? Kira