Part Number: 1528 Get the edge on high traction racing with the newest Fat Boys piston technology.   2.7mm thickness allows for a unique damping effect that is a huge benefit on high traction.  The added thickness and square edge Schelle design limits blow-by, so the oil is forced through the holes.  The added length of hole on the damping valve gives more pack on fast hits... all of this shines on high traction where you get more predictable cornering, and less abrupt body roll even when using larger hole valving. Precision CNC machined 13mm 2.7mm thick piston, 3 x 1.7mm holes. These pistons are sold 2 pcs per package and are hand marked "17" to denote the valving. Fits B7, B74.2, and B6.4 13mm shocks by Team Associated with "screw-on" piston.