Essex Designed AP Racing Radi-CAL Enduro Brake Kit - Front CP9668 (04-21 STI)
SKU: 95547341229

Essex Designed AP Racing Radi-CAL Enduro Brake Kit - Front CP9668 (04-21 STI)

Sale price$2166.27 Regular price$2406.97
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Description

Essex Designed AP Racing Radi-CAL Enduro Brake Kit - Front CP9668 (04-21 STI)Complete front Essex Designed AP Racing Radi CAL Competition Brake Kit for the Subaru WRX STI. Features AP Racing CP9668 Radi CAL six piston calipers, uses 25mm thick pad 355x32mm, 72 vane AP Racing disc Saves roughly 9 unsprung lbs. from nose vs. OEM brakes Every component designed to resist the heat of extended track sessions Pistons sized properly to allow for seamless integration with OEM master cylinder and ABS system Designed to work with OEM

Complete front Essex Designed AP Racing Radi-CAL Competition Brake Kit for the Subaru WRX STI.

  • Features AP Racing CP9668 Radi-CAL six piston calipers, uses 25mm thick pad
  • 355x32mm, 72 vane AP Racing disc
  • Saves roughly 9 unsprung lbs. from nose vs. OEM brakes
  • Every component designed to resist the heat of extended track sessions
  • Pistons sized properly to allow for seamless integration with OEM master cylinder and ABS system
  • Designed to work with OEM rear brakes

Advantages Over OEM Brake System

Our CP9668/355mm Radi-CAL Competition Brake Kit offers our customers the following advantages over the stock brake system:

  • Eliminates approximately 9 lbs. of unsprung weight from the car's nose
  • AP Racing Radi-CAL calipers are the stiffest, lightest, and most technologically advanced calipers available at any price
  • CP9668 calipers use a 25mm (1 inch) thick, commonly available brake pad shape
  • Ventilated, domed back, stainless steel pistons keep heat out of the brake fluid and provide an ultra-firm pedal
  • Mitigation of pad knockback via anti-knockback springs behind the caliper pistons
  • Anodized caliper finish that is resistant to wear and deterioration at elevated temperatures
  • Stainless steel caliper hardware for a long caliper service life under frequent pad change conditions
  • High temperature, low drag seals that will hold up to track temps= less rebuilding and longer service life
  • No dust boots to burn up
  • Simple pad change with two bolts or quick-change spring clip, no caliper removal required
  • Lifetime professional caliper rebuilding support by Essex (at a fee)- pull off your calipers, send them to us, we clean, inspect, and rebuild them
  • Available disc burnishing service ensures that your kit arrives ready to be installed and driven hard immediately
  • Championship winning, 72 vane, fully floating, AP Racing J Hook endurance racing discs with 12 attachment points to hat
  • Anti-knockback/anti-rattle disc attachment hardware
  • Replacement iron disc rings available at an extremely competitive replacement price
  • Disc metallurgy specifically designed to handle the temps typically seen on track offer a long service life
  • Highest quality, Spiegler stainless steel brake line with clear sheath that reduces compliance over OEM rubber design
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 95547341229

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4.7 ★★★★★
Based on 2135 reviews
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K
Verified Purchase
Kelly W.
Port Orchard, US
★★★★★ 3
Hard to assemble
Color: Grey
This is extremely hard to put together, but once its together it is pretty good. You will need to secure it to something. It falls over.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 6, 2026
M
Verified Purchase
Michael G.
Belleville, US
★★★★★ 5
Works well!
Color: Grey
Works great!
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Reviewed in the United States on May 4, 2026
G
Verified Purchase
Glass
Fort Morgan, US
★★★★★ 5
I stay on your foot they don’t slip in your shoe
Number of Items: 3, Color: White/Neutral (3-pairs), Size: Medium
This is the only socks I wear Under Armour because they stay in place I wear a size 8, but they’re more comfortable with a large instead of a medium, but I wear both because I have them already and you can pull them to stretch them out a little bit
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Reviewed in the United States on May 12, 2026
L
Verified Purchase
Lauren
Charlottesville, US
★★★★★ 5
Great fit, truly doesn’t slide off heel
Number of Items: 3, Color: White/Neutral (3-pairs), Size: Medium, Number of Items: 3, Color: White/Neutral (3-pairs), Size: Medium
I’ve scoured all the lands looking for a no-show sock that was 1) thin, 2) quality, soft, breathable material, 3) didn’t dig into my feet/heels, 4) doesn’t shrink, and most importantly 5) stays on the back of my heel without a bulky non-slip rubber piece and these check all the boxes! Perfect for low profile women’s work shoes like Keds, etc. Not low enough for most flats though. I wear a women’s size 9.
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Reviewed in the United States on April 19, 2025
E
Verified Purchase
Elliz
Phoenix, US
★★★★★ 5
So good - I’m buying MORE.
Number of Items: 3, Color: White (3-pairs), Size: Medium
I’m gonna give you more detail than you need about why I’m buying these socks again. I’ve been the mom of girl athletes. I’ve been a model and a fashion director. I’ve worn every brand of shoe on the planet and never found a shoe that did NOT find a vulnerable spot on my foot to rub raw. Even my beloved white Jack Purcell sneakers. With that said - I don’t like socks. I’ve bought a TON of them in 35+ years.....all major brands. They shift. They lose their shape. They get holes in them and wear out too fast. Not these. I retired this year, and knowing I’d be in sneakers a lot, traveling, sightseeing ...... I bought these 6 months ago and have worn them constantly. I’ve traveled with them. I’ve washed them in hot water and bleach. The socks are like brand new. They are exactly the right cut so as not to be seen in a basic sneaker. The little silicone patch on the heel stays put. Not once have I had to dig down into my shoe and pull the sock back up. The socks have stayed soft and EXACTLY the same as the day they were new. Like I said - I am back to buy them again. Great quality!
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Reviewed in the United States on January 20, 2021

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