How do I clean the car seat buckle?

To clean the buckle, recline the seat, locate the metal retainer, rotate it up through the shell and pad, and pull out the buckle strap from the front. Soak the buckle in a cup of warm water, gently agitating it while pressing the red button several times. Do not submerge the buckle strap or use soaps, household detergents, or lubricants. (Page 7)