KYB Strut Boot Kits keep your struts protected from dirt, dust, sand, salt and other road debris. These harmful elements cause abrasive wear to the polished shaft, upper seal & bushing. KYB Strut Boot Kits prevent these contaminants from entering the strut by covering the entire strut shaft in a highly durable plastic bellows. This can easily extend the life of the strut. The KYB Strut Boot Kit includes a poly foam travel-limiting bumper. It's designed to protect the strut from bottoming out and protects other components from extreme movement damage.