S = Hard Service Flexible Cord
SJ = Junior Hard Service Flexible Cord
T = Thermoplastic Insulation
O = Oil Resistant. “O” means only jacket is oil resistant; “OO” means jacket and conductor insulation are oil resistant
W = Moisture Resistant
D = Dry
H = Heater Cord
P = Parallel Cord
V = Vacuum Cable
N = Neoprene Insulation