Aluminum multi shock and push rod mount Rear rocker arm.
Now you do not need to change the rocker arm to change progressive rate. Just change the mounting position

Two red anodized aluminum bearing holders
two aluminum cams
four black 2mm button head screws
four silver cone shape spacers
two silver flat head screws

The key to Revo suspension performance is the progressive geometry built into the rockers. Increasing progressive rate over the stock progressive rockers or long travel rockers is as simple as bolting on a new setting of mounting plate.
For more combinations of adjustments P1 to p3 and Long Travel.
Change from firmness to Soft to suit your racing need. (Can use different push rod give you more flexibility) (P1 to p3 and Long Trave mount plate are sold separately. )