Perrin Diff Lockdown for 2008-2014 WRX/STi (PSP-SUS-535) VENDOR15 The matching washers are linked

The matching washers are linked below

The relay "trigger" can be connected to a ground or 12V signal as long as the other end of the low current relay coil wire is connected to an opposing source

APR carbon fiber front air dam for 2009-2011 R35 GTR models

5 through Evo 9 models

and fuel pulse dampers

Perrin Diff Lockdown for 2008-2014 WRX/STi (PSP-SUS-535) VENDOR15 The matching washers are linkedThe Perrin differential lockdown kit for 2008 2014 WRX STi adds drivetrain rigidity and precision to throttle input by reducing movement from the rear diff. Under tough driving conditions, the drivetrain and differential will twist. This causes a "squishy" or "spongy" feel on initial acceleration. This kit will lock the differential down for significantly reduced movement and better driver feel. Vehicle Fitment: 2008 2014 Subaru WRX 2008 2014 Subaru