These bolts are custom-machined from steel and polyurethane. They use existing holes in the rear subframe and unibody to lock the rear subframe together with the unibody. Sure, this adds noise and vibration. But the benefit is increased stability, better cornering, and improved predictability as the rear subframe stays put under heavy loading.
Why are they called "Botox Bolts?" We don't know.
Set of two bolts. Fits all 93-07 Impreza, including WRX and STI models. Does NOT fit 2008+ models.