Directional butting of the Energy SB20 seatpost’s 6066 aluminium shaft gives it thicker walls fore and aft for stiffness and thinner walls at the sides to cut weight. A forged and machined alloy head is bonded into the top of the shaft. Features 3D forged and CNC machined AL6066 w/ alloy head Directionally butted tube (thicker wall fore and aft) Finish: black anodized finish 20mm Setback Weight: 275g (diameter 27.2mm)