Genuine Honda slave cylinder. ScienceofSpeed offers both generations of slave cylinder.
Differences:
2000-03 (North America) and 2004-09 (international) "AP1" slave cylinder does not use a delay valve.
2004-09 (North America) "AP2" slave cylinder includes a delay valve - the delay valve was added to increase the ease of engaging the heavier flywheel used in these years.
The 2000-03 slave cylinder can be used on a 2004-09 model when lighter flywheels are used. This is recommended because the delay valve will cause the clutch to engage slower than the lighter flywheel allows the engine to slow down.