K-type Thermocouple wire for making thermocouple or extension wire, up to 1292 F (700 C) Chromel / Alumel type K thermocouple wire with Standard Accuracy (whichever is greater): +/- 2.2C or +/-.75% The wires are AWG 24 (0.51 mm) in diameter ANSI color coded braided high temperature fiberglass insulation, red = -, yellow = + Sold in 10 yard precut rolls