TGGT high temperature wire and MG high temperature wire are single-core leads for protected equipment wiring in severe heat. This family combines 250°C TGGT constructions in 300 V and 600 V versions with 450°C mica-glass MG constructions in 300 V and 600 V versions. Each model has a distinct insulation system and size range.
TEBAOFLEX can manufacture these constructions to the stated material and dimensional requirements. Selection must be based on model, circuit voltage, continuous and peak temperature, conductor size, routing, termination and surrounding atmosphere. The style numbers below identify construction references; the ordered production specification governs the finished wire.
Which TGGT or MG High-Temperature Wire Should You Choose?
| Model | Wire family | Voltage | Temperature | Reference size range | Primary selection reason |
|---|---|---|---|---|---|
| UL 5256 | TGGT | 600 V | 250°C | 20–2 AWG | Higher-voltage PTFE and fiberglass insulated lead wire for ovens and industrial hot zones. |
| UL 5257 | TGGT | 300 V | 250°C | 20–2 AWG | 300 V TGGT heater and appliance wire with a thinner PTFE reference wall. |
| UL 5359 | MG | 600 V | 450°C | 12 AWG | Mica-glass insulated lead for very-high-temperature industrial equipment. |
| UL 5360 | MG | 300 V | 450°C | 24 AWG | Small-gauge mica-glass lead for heaters and similar hot-zone equipment. |
What Are TGGT and MG High-Temperature Wires?
TGGT wire uses a flexible stranded nickel-plated copper conductor, wrapped PTFE fluoropolymer tape, fiberglass yarn and a treated fiberglass braid. It is designed for protected wiring where temperatures can reach 250°C. Engineers and buyers may also search for this construction as PTFE fiberglass braided wire, 250°C lead wire, oven lead wire, high-temperature appliance wire, 600V TGGT wire or 300V TGGT heater wire.
MG wire replaces the PTFE insulation system with glass-reinforced phlogopite mica tape and uses a fiberglass braided outer covering. The reference MG models on this page use flexible stranded 27% nickel-plated annealed copper and are designed around a 450°C temperature reference. Related search terms include mica glass insulated wire, 450°C heater wire, kiln wire, furnace lead wire, nickel-plated copper high-temperature wire and fiberglass braided mica wire.
TGGT and MG Construction Comparison
| Component | TGGT construction: UL 5256/5257 | MG construction: UL 5359/5360 |
|---|---|---|
| Conductor | Flexible stranded nickel-plated annealed copper | Flexible stranded 27% nickel-plated annealed copper |
| Primary insulation | PTFE fluoropolymer tape | Glass-reinforced phlogopite mica tape |
| Additional insulation layer | Wrapped fiberglass yarn | No separate fiberglass-yarn layer stated in the reference construction |
| Outer covering | Fiberglass braid treated with a high-temperature saturant, natural tan | Fiberglass braid treated with a high-temperature saturant, natural tan |
| Temperature reference | 250°C | 450°C |
| Mechanical duty | Protected fixed internal wiring; not a continuous-flex or reeling cable | Protected fixed hot-zone wiring; routing and handling require engineering review |
UL 5256 TGGT 600 V, 250°C Reference Specifications
UL 5256 is the 600 V TGGT option. The values below reproduce the supplied metric reference for conductor size, strand count, insulation thickness, braid thickness, nominal finished diameter and approximate weight.
| AWG | Strands | Insulation (mm) | Braid (mm) | Nominal OD (mm) | Approx. weight (kg/km) |
|---|---|---|---|---|---|
| 20 | 10 | 0.18 | 0.13 | 1.78 | 15 |
| 18 | 16 | 0.18 | 0.13 | 1.98 | 19 |
| 16 | 26 | 0.28 | 0.13 | 2.34 | 25 |
| 14 | 41 | 0.28 | 0.13 | 2.87 | 34 |
| 12 | 65 | 0.30 | 0.13 | 3.23 | 48 |
| 10 | 105 | 0.30 | 0.13 | 3.94 | 71 |
| 8 | 133 | 0.33 | 0.13 | 5.33 | 107 |
| 6 | 133 | 0.36 | 0.15 | 6.73 | 179 |
| 4 | 133 | 0.36 | 0.15 | 8.13 | 260 |
| 2 | 133 | 0.36 | 0.15 | 9.91 | 402 |
UL 5257 TGGT 300 V, 250°C Reference Specifications
UL 5257 is the 300 V TGGT option. It shares the same broad conductor, PTFE, fiberglass-yarn and fiberglass-braid construction concept while using the model-specific dimensions listed below.
| AWG | Strands | Insulation (mm) | Braid (mm) | Nominal OD (mm) | Approx. weight (kg/km) |
|---|---|---|---|---|---|
| 20 | 10 | 0.10 | 0.13 | 1.63 | 13 |
| 18 | 16 | 0.10 | 0.13 | 1.83 | 18 |
| 16 | 26 | 0.10 | 0.13 | 2.18 | 24 |
| 14 | 41 | 0.10 | 0.13 | 2.72 | 33 |
| 12 | 65 | 0.20 | 0.13 | 3.07 | 45 |
| 10 | 105 | 0.20 | 0.13 | 3.78 | 67 |
| 8 | 133 | 0.20 | 0.13 | 5.18 | 101 |
| 6 | 133 | 0.28 | 0.15 | 6.58 | 173 |
| 4 | 133 | 0.28 | 0.15 | 7.98 | 253 |
| 2 | 133 | 0.28 | 0.15 | 9.75 | 387 |
UL 5359 and UL 5360 MG 450°C Reference Specifications
The supplied MG references define two distinct configurations: a 12 AWG, 600 V model and a 24 AWG, 300 V model. These dimensions should not be extended to unlisted sizes without an approved production drawing.
| Model | Voltage | AWG | Strands | Insulation (mm) | Braid (mm) | Nominal OD (mm) | Approx. weight (kg/km) | Temperature |
|---|---|---|---|---|---|---|---|---|
| UL 5359 | 600 V | 12 | 65 | 0.41 | 0.18 | 3.68 | 46 | 450°C |
| UL 5360 | 300 V | 24 | 7 | 0.30 | 0.18 | 1.65 | 7 | 450°C |
TGGT vs. MG Wire: Practical Selection Guide
| Decision factor | Choose TGGT when | Choose MG when |
|---|---|---|
| Temperature | The confirmed conductor location remains within the 250°C construction reference. | The protected hot zone requires the listed 450°C mica-glass construction. |
| Insulation preference | PTFE tape with fiberglass yarn is specified. | Glass-reinforced phlogopite mica tape is specified. |
| Size range | The circuit requires a reference size from 20 through 2 AWG. | The project matches the listed 12 AWG or 24 AWG MG configuration. |
| Voltage | Select UL 5256 for 600 V or UL 5257 for 300 V. | Select UL 5359 for 600 V or UL 5360 for 300 V. |
| Application | Ovens, cooking equipment and industrial processing equipment with severe but controlled hot spots. | Heaters, iron and steel mills, glass plants, cement kilns and comparable very-hot protected equipment zones. |
Voltage and temperature are only two selection factors. The full equipment design must also consider current capacity, bundling, ambient temperature, terminal temperature, heat cycling, vibration, mechanical protection and the atmosphere around the wire.
Typical Applications
- Internal wiring of commercial, industrial and household ovens and cooking equipment.
- Electric heaters and heating elements requiring protected high-temperature lead connections.
- Industrial processing equipment with localized severe hot spots.
- Iron and steel mills, glass plants and cement kilns where the selected MG construction matches the hot-zone requirement.
- Furnace, kiln and thermal-process instrumentation or power leads installed within the confirmed electrical and mechanical limits.
These are application examples, not universal suitability statements. The wire is intended for protected equipment wiring. It should not be assumed suitable for exposed outdoor routing, direct burial, immersion, continuous flexing, torsion, reeling, cable chains or unsupported pulling loads.
Installation and Handling Limits
- Route the braid away from sharp edges, crushing points and abrasive movement.
- Use stripping and termination methods compatible with wrapped PTFE or mica-glass insulation; do not nick the conductor.
- Confirm the maximum temperature at the conductor and terminal, not only the surrounding air temperature.
- Account for temperature cycling, vibration, bundling, enclosure conditions and heat from adjacent components.
- Protect the completed connection from contamination and mechanical stress appropriate to the equipment.
- Verify that every terminal, splice, sleeve and nearby component is suitable for the actual operating conditions.
Custom Production and Ordering Information
TEBAOFLEX can review the required model, conductor size, conductor construction, braid treatment, printed identification, cut length, coil or reel format and export packaging. Availability is confirmed against the final technical requirement. If a requested size or construction is outside the tables above, it must be evaluated as a separate custom design rather than represented as an existing table value.
| RFQ detail | What to provide | Why it matters |
|---|---|---|
| Model and voltage | UL 5256, 5257, 5359 or 5360; 300 V or 600 V | Determines the reference construction and insulation system. |
| Conductor size and load | AWG size, current, duty cycle and allowable voltage drop | Supports electrical and thermal selection. |
| Temperature profile | Continuous, peak, terminal and ambient temperatures | Separates a 250°C TGGT requirement from a 450°C MG requirement. |
| Installation | Fixed or moving, routing, bend space, abrasion, vibration and protection | Confirms whether this protected fixed-wiring family is appropriate. |
| Environment | Oils, process chemicals, moisture, atmosphere and contamination | Allows material compatibility and protective measures to be reviewed. |
| Order details | Marking, length, packaging, quantity and required production documents | Defines manufacturing and commercial requirements. |
Related High-Temperature Wire Options
- UL 10371 PFA 250°C 1000V high-temperature wire
- UL 10362 PFA 250°C 600V high-temperature wire
- UL 3530 silicone 150°C 600V high-temperature wire
- High-temperature and specialty cable range
Frequently Asked Questions
What is TGGT high-temperature wire?
TGGT is a single-core high-temperature lead construction using a nickel-plated stranded copper conductor, wrapped PTFE insulation, fiberglass yarn and a treated fiberglass braid. The two TGGT models on this page are rated by their reference construction for 250°C and either 300 V or 600 V.
What is MG high-temperature wire?
MG wire uses a nickel-plated stranded copper conductor, glass-reinforced phlogopite mica tape and a treated fiberglass braid. The listed MG models provide 450°C constructions for either 300 V or 600 V protected equipment wiring.
What is the difference between UL 5256 and UL 5257?
Both are 250°C TGGT constructions in 20–2 AWG. UL 5256 is the 600 V model, while UL 5257 is the 300 V model and has its own model-specific insulation thickness and finished dimensions.
What is the difference between UL 5359 and UL 5360?
Both are 450°C MG mica-glass constructions. The supplied UL 5359 reference is 600 V, 12 AWG and 3.68 mm nominal OD; the UL 5360 reference is 300 V, 24 AWG and 1.65 mm nominal OD.
Can TGGT or MG wire be used in continuous movement?
These references describe protected internal equipment wiring, not a continuous-flex, torsion, reeling or cable-chain cable. Submit the motion profile if the wire will move during service so a suitable construction can be evaluated.
Which information is needed for a quotation?
Provide the model, voltage, AWG size, current, continuous and peak temperature, terminal type, installation method, surrounding environment, length, quantity, marking and packaging requirements.
Send Your TGGT or MG Wire Requirements
Send the required model, voltage, temperature profile, conductor size, equipment type, routing conditions, length and quantity. The TEBAOFLEX technical team will review the construction and confirm a production specification before quotation.





