Home Improvement → Liquid tight conduit question

Does it come in any size smaller then 3/4?

1/2"...

Just to clarify...liquidtight is available in all trade sizes. The trade size is the internal diameter (ID), not the OD.

It is available in 3/8" also, but that is not "legal" for general use, and is generally restricted to inclusion in equipment by OEMs, who are not bound by the NEC.

please, what are you trying to do?

OEManufacturers still often follow UL rules,

and the smaller wires and smaller conduits are typically used for circuits less than 24 volts.

if 115 volts, typically the restriction is no smaller wire than 18 gauge, no matter how low the current is.

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and, in general, unless you are doing something extreme, you can get by if you limit your conduit fill to less than 43%, leaving 57% airspace.