Graco Century Owner's Manual page 70

INFANT RESTRAINT METAL AND PLASTIC PARTS may be
cleaned by wiping with a mild soap and water solution.
DO NOT USE BLEACH. Use of bleach may weaken plastic parts.
HARNESS STRAPS may be spot cleaned or replaced.
DO NOT IMMERSE THE HARNESS STRAPS IN WATER. Doing so
may weaken the harness straps.
DO NOT USE INFANT RESTRAINT without seat pad.
CONTINUOUS USE OF INFANT RESTRAINT MAY CAUSE
DAMAGE TO VEHICLE SEAT. Use an infant restraint mat, towel
or thin blanket to protect upholstery.
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