Caliper bushing kit. Left.2016-18. Rear. Right.2016-18. A Bushing, typically made of rubber, used to provide a surface for the disc brake Caliper guide pin to move freely. A Kit containing disc brake Caliper guide pin boots. Disc Brake Caliper Bushing. Disc Brake Caliper Pin Seal.. mount. Disc Brake Guide Pin Seal. Disc Brake Slide Pin Boot. Included with: Caliper.