JRC JMA-5312-6/6HS Installation Manual page 20

c) Use of washer and corrosion-resistant measures
• At the location where a bolt's head or nut comes in contact with the antenna chassis' legs
and the mount base, insert a plain washer which fits the bolt; and, at the location where
the nut comes in contact with the plain washer, insert a spring washer, and then securely
tighten the nuts (Fig.10).
• To prevent corrosion due to the contacts between different metals, such as the antenna
chassis' legs, installation surface, bolts, nuts, etc., cover the bolt's head and nuts with
sealant (Fig.10).
Fig.10 Use of washer and corrosion-resistant measures
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