FLEXIBLE CORD AND CABLE
NEC® Article 400, Table 400.4

E As first letter — Elevator cable
E After first letter — Thermoplastic elastomer insulation and jacket
EV Electric Vehicle Cable
H Heater cord
NI "Non-Integral," used for parallel cords such as Type NISPT-1 to denote
insulated conductors and jacket are separate
O Oil resistant. Single "O" means jacket only is oil resistant; double "O" means
jacket and conductor insulation are oil resistant
P Parallel conductor cord
S Extra hard usage Flexible Cord
SJ Hard usage Flexible Cord
SV Not hard usage Flexible Cord
T As the first letter — Tinsel cord. Single flattened 27 AWG conductor wound
around insulating core, for very low current, highly flexible application
T After the first letter — Thermoplastic insulation and jacket
-1, -2, -3 Insulation thickness for parallel cords, thinnest to thickest. Actual insulation
thickness varies with cord type and AWG size
XTW Parallel cord for decorative lighting strings
CXTW Twisted pair cord or single conductor for decorative lighting strings
W As the Last letter — Suitable for use in wet locations and sunlight resistant
W As the only letter — Portable Power Cable
Examples: SJTO–Hard usage, thermoplastic, oil resistant jacket
SPT-2–Parallel Cord, thermoplastic