Insulated Thermocouple & Extension Wire Insulation types

†Thermocouple extension grade wire is only calibrated up to 400°F (204°C).

Image	Single Conductor		Duplex Conductors		Temperature Rating†		ANSI Color Coded	Physical Properties
Image	Insulation	Impregnation	Insulation	Impregnation	Continuous	Single Reading	ANSI Color Coded	Abrasion Resist.	Moisture Resist.	Chemical Resist.
	Glass Braid	Silicone Modified Resin (retained to 400°F [204°C])	Glass Braid	Silicone Modified Resin (retained to 400°F [204°C])	900°F (482°C)	1000°F (538°C)	Yes	Fair	Good	Good
	Double Glass Wrap	Silicone Modified Resin (retained to 400°F [204°C])	Glass Braid	Silicone Modified Resin (retained to 400°F [204°C])	900°F (482°C)	1000°F (538°C)	Yes	Fair	Good	Good
	High Temp Glass Braid	High Temp Varnish (retained to 400°F [204°C])	High Temp Glass Braid	High Temp Varnish	1300°F (704°C)	1600°F (871°C)	Yes	Good	Fair	Good
	Polyvinyl (PVC)	—	Polyvinyl (PVC)	—	-20 to +221°F (-29 to 105°C)	221°F (105°C)	Yes	Good	Excellent	Good
	FEP Extr.	—	FEP Extr.	—	400°F (204°C)	500°F (260°C)	Yes	Excellent	Excellent	Excellent
	Kapton®	—	Kapton®	—	500°F (260°C)	800°F (427°C)	Yes (Indiv. only)	Excellent	Excellent	Excellent
	Polyvinyl (PVC)	—	Polyvinyl (PVC) Twisted	—	-20 to +221°F (-29 to +105°C)	221°F (105°C)	Yes	Good	Excellent	Good
	Vitreous Silica Fiber	—	Vitreous Silica Fiber	—	1600°F (871°C)	2000°F( 1093°C)	No	Fair	Fair	Good
	Ceramic Fiber	—	Ceramic Fiber	—	2200°F (1204°C)	2600°F (1427°C)	No	Good	Fair	Good