Kyosho W5303-10 Big Bore Shock Piston 3-Hole (2)

Kyosho W5303-10 is a genuine pair of three-hole shock pistons for Kyosho's big bore dampers, drilled at 1.4mm. The piston meters oil flow as the shaft strokes, so hole count and diameter set the damping character. Three 1.4mm holes flow more oil than a two-hole piston, producing a freer, more responsive damper that lets the suspension react quickly to bumps and generate mechanical grip. It is the usual choice for rough or low-traction tracks where a packed shock would skate across the surface.

Pistons and oil weight are tuned together, and swapping pistons often gives a cleaner result than moving to extreme oil weights, since hole count stays consistent as oil warms through a run. These install as a direct-fit tuning option in Kyosho's big bore shock sets, fitting the Ultima RT6, RB6, and SC along with the Lazer ZX-5 series and the FS2 SP and SC-R SP models. Package includes two pistons.