HKS Intercooler Pipe Kit. Replacing the rubber inlet & outlet hoses with aluminum hoses restrains its expansion to improve the throttle response and smoothly increase the boost pressure. Also, aluminium hoses can be securely connected even under a high pressure. Factory rubber hoses are replaced with aluminium pipes and silicone joint hoses, and they are secured with reinforced hose bands. HKS original casting inlet pipe allows smooth layout.