For the Silvia model, one of these 560 mm tubing (approximately 22 inches) is used to go from the water reservoir to the inlet side of the pump. Another, separate, 560 mm tubing goes from the expansion ("Over Pressure") valve back to the reservoir.
But of course this is a generic part and can be used in a number of applications after ensuring the fittings are the correct size. Also works well on the exhaust fitting of 3 way solenoids. One per purchase.
WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.