FASWORX Power Trim Line Service Kit (Replaces 3889431) Protect your marine hydraulic system from pressure loss and fluid leaks with the FASWORX Power Trim Line Service Kit. Designed as an exact drop-in replacement for Volvo Penta 3889431, this kit provides the essential seals required when servicing your trim cylinders or replacing your trim hoses. Over time, the original O-rings and retainers degrade due to harsh marine environments and high hydraulic pressures, leading to sluggish tilt performance or complete power trim failure. This 16-piece kit includes 8 specialized high-pressure O-rings and 8 retainer cups, giving you exactly what you need to tightly seal the connections between your power trim lines, trim pump, and cylinders. Required for Hose Replacement: If you are installing a replacement trim hose kit (such as Volvo Penta 21481309), the factory hoses do not include these specific seals. The FASWORX service kit provides the missing hardware needed to complete the installation. Compatibility Summary: Fits 2007+ Volvo Penta models: SX Outdrives: SX-A, SX-ALT, SX-B DPS Outdrives: DPS-A, DPS-A OXi, DPS-B, DPS-B1 Transom Shields (TSK): TSK-A, TSK-B, TSK-C, TSK-SK Fitment Notice: Always double-check your outdrive or transom shield serial number to guarantee accurate fitment for your specific setup.