Customarily used.

Customarily used. A semitrailer or trailer is treated as customarily used in connection with a highway motor vehicle if the vehicle is equipped to tow the semitrailer or trailer.
A semitrailer or trailer is treated ascustomarily usedin connection with a highway motor vehicle if the vehicle is equipped to tow the semitrailer or trailer.

Source

26 CFR § 41.4482(c)-1


Scoping language

None
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