Honda Harmony HS520A Owner's Manual page 49

TECHNICAL & CONSUMER INFORMATION
Replacement Parts
The emission control systems on your new Honda engine were
designed, built, and certified to conform with EPA and California
emission regulations. We recommend the use of genuine Honda parts
whenever you have maintenance done. These original-design
replacement parts are manufactured to the same standards as the
original parts, so you can be confident of their performance. The use of
replacement parts that are not of the original design and quality may
impair the effectiveness of your emission control system.
A manufacturer of an aftermarket part assumes the responsibility the
part will not adversely affect emission performance. The manufacturer
or rebuilder of the part must certify that use of the part will not result in
a failure of the engine to comply with emission regulations.
Maintenance
Follow the maintenance schedule on page21. Remember that this
schedule is based on the assumption that your machine will be used
for its designed purpose. Sustained high-load operation will require
more frequent service.
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