Or lack thereof. My airboot has very deep scratches on the inner surface. At first I thought it was cracking, but they are actually deep scratches. Is this just poor quality rubber or a dirty mold when the part was made? Has anyone else noticed this? The assembly work is shoddy, you can see the carb impression in the rubber. Notice how crooked the rim is; the end of the boot was not squared up on the back of the carb.