Thomson Elite InLine Seatpost - Black Over 40% stronger on ultimate strength test than the strongest production seatposts on the market. Over double the fatigue life of any other production models we tested. The tube and head of the Thomson seatpost are integral-machined from one single piece of high strength 7000 series aluminum. The head is not pressed or bonded in. This allows for superior strength and minimum weight, allowing higher strength at low weights. Lightweight - approximately 188 grams (250 length) for road bikes and 228 grams (330 length) for mountain bikes. Natural ellipse bore inside tube for optimum strength to weight ratio. We have a long 1.614 inch (41mm) seat rail grip length. This helps prevent seat rail bending from impact loads. Most other brand seatposts have grip lengths of0.500 inch or more shorter than our grip length. The Thomson seatpost design incorporates a bending fuse to prevent catostrophic failure. All other brand seatposts we tested - every one of them - failed in catastrophic failure with the seat and clamp components - and sometimes pieces of the tube and head - flying off in all directions. This type of failure would dump the rider. Thomson seatpost has a clamp, head, and upper tube strong enough to withstand 350 foot-lbs of torque. The tube will start to yield and bend at the seat tube clamp at about 250 foot-lbs of torque. Remember all other brand posts we tested flew apart at less than 150 foot-lbs of torque. Under severe impact the Thomson seatpost would bend slightly, the ride could continue.