It took advance negotiation with the AHJ, but I have used Appleton STB***SR- or STN***SR-series “basket-grip” liquidtight flexible-metal conduit connectors for (temporary/one-year) vertical-only spans where the bottom ends were non-anchored floor-elevation equipment.
Page 7-8
www.appletonelec.com/pdf/ST-2thru13.pdf [Hubbell and T&B also make ‘em.]
Here’s one consideration for article-400 wiring—in the case of flexible cord for “drop” duty, it is well worth avoiding the pervasive “commodity-grade” type-S** neoprene- or vinyl-jacketed cord. A lot of that stuff has embarrassingly {and litigiously} poor durability—used inside or out.
[This message has been edited by Bjarney (edited 06-22-2004).]