Mustang Survival MIT 70 Manuel D'utilisation page 21

For MD4042
You should test the automatic inflation system in the water at the
beginning of each boating season. This includes inspecting the
bobbin's expiration date and discarding if past the expiration date
OR discarding if the element has been exposed to gas, oil, water, or
high humidity. By doing this, you demonstrate that the automatic
inflation system is still working properly and reduce the likelihood of
premature inflation and its associated dangers.
For Both MD4041 and MD4042
Check the manual inflation system (with CO2 cylinder removed) to
determine that the lever arm and piercing pin move freely when
moving the lever (attached to the pull tab) several times (pull lever
down and up for MD4041, push up lever for MD4042) determine
that the lever arm moves freely. There should be no binding of the
mechanical parts.
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