Tapout Now Stocks Eibach Special Edition Pro Kit lowering springs for both CT4-V Blackwing ad CT5-V Blackwing! Expected drop = 0.7 inch (17.8 mm). The Eibach PRO-KIT is a premium line of lowering springs designed to enhance the performance and appearance of your vehicle. Whether you’re a car enthusiast looking to improve the handling of your daily driver or motorsports competitor looking for an edge on the track. the Eibach Pro Kit has you covered.