This "MAX IV SP" is the ultimate sport model for such a high grip radial tire. It will transfer the feelings straight to driver all kinds of information such as tire, road surface condition and traction. It’s a perfect street sport model suspension for people who love to drive fast but still want comfort.
  
Single Tube Damper Design

Mono tube dampers allow for more accurate and stable control and adjustment of dampening. Lower ride height and centre of gravity gives a more stable ride.
Dust Boot
Protect the shaft from the flying stones.
PNE Coating

Using this special surface coating provides 5 times better durability over standard galvanising. This prevents build-up around the threads of the adjustment areas allowing for easier height adjustment.

M Shaft (Φ46 normal type)

With the new design of cylinder shaft since the HIPERMAX M-1, MAX IV increased the cylinder shaft size to have a firm damping even at a little stroke range by optimizing the oil pressure characteristic. We mainly adopted this to the rear damper that can have a better driving experience.
  
Adopted Pillow Ball Upper Mount
  
For more accurate and sharp steering.
  
New Design Needle

Newly designed needle has been used to revise the very low speed and middle and high speed dampening which is key to a comfort ride.
  
Reduction of Unsprung Weight
In order to reduce unsprung weight, bracket, ride height adjusters and lock nuts are made from aluminium. (Not for all vehicles)

30 Step Damping Force Adjustment
30 levels of dampening adjustment allow fine tune adjustment for street, circuit winding roads, highway, or the weight of the vehicle.

Spring Rate
Front: 12k
Rear: 10k
 
THIS PART FITS
  
2015-2018 STI HKS Hipermax IV SP Coilovers
  
2015-2018 WRX HKS Hipermax IV SP Coilovers