I'm installing an under eve outdoor floodlight, the standard two bulb type, going to use 150W floods. I also plan on using two switches so I can control each lamp separately. It will be wired with four #14 THHN/THWN-two hots, neautral and eqpt. Ground. The wire will be in conduit except for the last four feet where I need to use FMC. The lights will not be continuous use.

I planned on using trade size 3/8" FMC. Table 348.22 alllows up to four wires plus a ground of the same size based on my wire selection when using fittings outside conduit. However, I know there is more to it than just fill amount.

Based the 300W total is the 3/8" acceptable or should I use 1/2" FMC?

1/2" sealtite

1/2" flexible nonmettalic conduit would also be a good choice...it's listed for exterior
use. I would not use flexible metal conduit for an exterior application. Most if not all outlet boxes have 1/2" openings at smallest.

3/8" FMC with outside fittings will work fine, as you propose, providing this is not a wet location.

FMC was allowed in wet location prior to the 2008 Edition of the NEC.

If this is a damp location, you may use FMC.

I tried to cover everything in my post, but omitted the fact that the small run of FMC will be IN the eve, not exposed to the elements, and connected to a surface mount flood--so my question is answered. Thanks for all the responses, much appreciated.