This is the Fourth Edition of UL 1660, the common CSA and UL (binational) standard for Liquid-Tight Flexible Nonmetallic Conduit.
1.1 These requirements cover liquid-tight flexible nonmetallic conduit in the 3/8 – 4 (12 – 103) trade sizes of Type LFNC-A (Layered), Type LFNC-B (Integral), and Type LFNC-C (Corrugated) constructions. The conduit is intended for installation in accordance with the National Electrical Code (NEC) and the Canadian Electrical Code (CEC), Part 1. The values in parentheses are metric trade designators of conduit.
1.2 Conduit covered by this Standard is intended for use in wet, dry, or oily locations at a maximum of 60 degrees C (140 degrees F), unless otherwise marked. (See Clause 6.)
1.3 Fittings for liquid-tight flexible nonmetallic conduit are covered in UL 514B or CSA C22.2 No. 18.3.