1A STAR technische Kunststoffe GmbH in 57399 Kirchhundem, Germany, is the manufacturer of DURAVOLTA. DURAVOLTA is a halogen-free, flame-retardant polypropylene film for electrical insulation, developed by 1A STAR and sold under its own brand. From a thickness of 0.43 mm, DURAVOLTA achieves the flammability rating UL 94 V-0. DURAVOLTA 25 at 0.25 mm achieves VTM-0, the best class of the test method that UL 94 provides for thin films instead of the V test. DURAVOLTA is extruded into films and sheets in Germany to its own formulation; in its own plant in Kirchhundem, 1A STAR turns them into die-cut parts, bent parts and self-adhesive parts to drawing. The formulation is registered with UL under File number E354767. DURAVOLTA has been monitored by UL since 2014 and is approved for the USA and Canada.
From formulation to finished part
Formulation. The raw material for DURAVOLTA is compounded to the proprietary DURAVOLTA formulation. The formulation is part of the UL listing and may not be changed without UL's approval. Every raw material delivery is checked at goods-in for batch, melt flow rate (MFR) and appearance.
Extrusion. DURAVOLTA is extruded in Germany to this formulation into rolls and sheets.
Die-cutting, cutting, milling. 2D parts to drawing are produced on die-cutting machines, CNC plotters and CNC milling machines in 1A STAR's own plant, as one-offs as well as in series.
Creasing and bending. Bent parts are creased and formed on 1A STAR's own bending machines. This turns a flat film into cost-effective three-dimensional insulating parts such as enclosures, ducts and covers.
Laminating and finishing. On its own laminating systems, 1A STAR mainly finishes DURAVOLTA with a self-adhesive backing. Laminates with other materials are also possible.
Printing, embossing, welding. 1A STAR also carries out these processes in its own plant.
Injection moulding and thermoforming. 1A STAR also supplies injection-moulded and thermoformed parts made of DURAVOLTA. These two processes are carried out by a partner company.
Product range
DURAVOLTA is available as rolls, as sheets, as granules and as finished parts to drawing.
| Type | Thickness | UL 94 (V-0, VTM-0 for thin films) | Rolls (width × length) | Sheets |
|---|---|---|---|---|
| DURAVOLTA 10 | 0.10 mm | not UL rated | on request, not stocked | on request, not stocked |
| DURAVOLTA 12 | 0.125 mm | VTM-0 (in-house test, UL listing in preparation) | 610 mm × 1,220 m | stocked |
| DURAVOLTA 25 | 0.25 mm | VTM-0 | 610 mm × 610 m | stocked |
| DURAVOLTA 43 | 0.43 mm | V-0 | 610 mm × 305 m | 2,000 × 1,000 mm from stock |
| DURAVOLTA 76 | 0.76 mm | V-0 | on request, not a stock item | 2,000 × 1,000 mm from stock |
| DURAVOLTA 100 | 1.00 mm | V-0 | on request, not a stock item | 2,000 × 1,000 mm from stock |
| – | 2.00 mm | not UL rated | – | 2,000 × 1,000 mm from stock |
| – | 3.00 mm | not UL rated | – | 2,000 × 1,000 mm from stock |
The type name gives the thickness in hundredths of a millimetre: DURAVOLTA 43 is 0.43 mm thick, DURAVOLTA 100 is 1.00 mm thick.
1A STAR can also supply the 0.76 mm and 1.00 mm thicknesses as rolls. They are not stock items, however. At these thicknesses the material keeps the curl from the roll, and it usually cannot be removed easily from die-cut or cut parts. For finished parts from 0.76 mm, 1A STAR therefore recommends sheets.
The 2 mm and 3 mm sheets are available from stock but are not UL rated; the UL rating covers up to 1.1 mm. Experience shows that the fire behaviour of a plastic tends to improve rather than deteriorate with increasing thickness. If you need proof of UL 94 V-0, choose DURAVOLTA 43 to DURAVOLTA 100. 1A STAR produces thicknesses above 3 mm on request.
DURAVOLTA 10 and DURAVOLTA 12 are available but not yet UL rated. According to internal tests, DURAVOLTA 10 achieves class VTM-0; an official test and rating by UL can be arranged if required.
1A STAR supplies DURAVOLTA granules from a quantity of 500 kg.
Colour. DURAVOLTA is produced in natural / white, and the UL rating applies to this version. Black DURAVOLTA is not part of the product range. In almost all cases the white version serves the same purpose, with one advantage: tracking and burn marks are easier to spot on white material. If your application nevertheless requires black, please contact 1A STAR.
UL listing and flammability rating by thickness
DURAVOLTA is listed with UL under File number E354767, in categories QMFZ2 for the USA and QMFZ8 for Canada. The listing has existed since 28 October 2014 and is continuously monitored by UL.
The flammability rating depends on the thickness. From 0.43 mm, DURAVOLTA achieves UL 94 V-0. DURAVOLTA 25 at 0.25 mm is rated UL 94 VTM-0.
Looking for a V-0 film in 0.125 or 0.25 mm? For films of this thickness, UL 94 provides the VTM method instead of the V test. It was developed to allow a statement comparable to V-0 for thin films as well, because in the V test thin films deform so much that the result would be meaningless. DURAVOLTA 25 achieves the best class of the VTM method, VTM-0. Whether VTM-0 meets your requirement depends on your specification: some require "V-0 or VTM-0", others explicitly V-0. In the second case, choose DURAVOLTA from 0.43 mm.
Explained in detail: UL 94 V-0 for thin films – what VTM-0 means
DURAVOLTA is halogen-free according to IEC 61249-2-21, and has been since its introduction. There has never been a halogenated version. DURAVOLTA is also REACH and RoHS compliant.
Values from the UL listing
| Thickness | UL 94 | HWI (PLC) | HAI (PLC) | RTI electrical | RTI mechanical |
|---|---|---|---|---|---|
| 0.1 mm | none | 4 | – | – | – |
| 0.15–0.25 mm | VTM-0 | – | – | – | – |
| 0.25 mm | – | 2 | 0 | – | – |
| 0.4–0.9 mm | V-0 | 2 | 0 | 120 °C | 105 °C |
| 1.0–1.1 mm | V-0 | 0 | 0 | 120 °C | 105 °C |
| Property | Value | Test standard |
|---|---|---|
| Dielectric strength | 43 kV/mm | ASTM D149 |
| Volume resistivity | 1.0 × 10¹⁴ ohm·cm | ASTM D257 / IEC 60093 |
| Comparative tracking index CTI | PLC 0 | UL 746A |
| High-Voltage Arc Tracking Rate (HVTR) | PLC 0 | UL 746A |
| Arc resistance (D495) | PLC 6 | UL 746A |
The flammability ratings also apply according to IEC 60695-11-10.
Reprinted from Product iQ with permission from UL Solutions. ©2026 UL LLC.
How to read the table. UL rates tracking resistance and arc behaviour in performance level categories (PLC), where 0 is the best level. For the comparative tracking index CTI, DURAVOLTA achieves the highest level, PLC 0, which corresponds to 600 V or more. The relative thermal index (RTI) is 120 °C for the electrical properties and 105 °C for the mechanical properties. For parts under mechanical load, the 105 °C value applies.
Test certificate. 1A STAR issues a test certificate with the delivery on request.
DURAVOLTA in control cabinet construction
In control cabinet construction, DURAVOLTA is used for four tasks:
- Busbar insulation: DURAVOLTA insulates busbars from each other and from the enclosure.
- Insulation between components: cut pieces and die-cut parts made of DURAVOLTA separate live components from each other.
- Partition walls: DURAVOLTA sheets and bent parts form partitions between areas of the control cabinet.
- Ventilation ducts: bent DURAVOLTA parts guide the cooling air three-dimensionally through the control cabinet.
In all four cases, DURAVOLTA also acts as flame protection: from a thickness of 0.43 mm, the material self-extinguishes according to UL 94 V-0.
DURAVOLTA as an alternative to Formex GK
The Formex GK types are named after their thickness in thousandths of an inch. GK-17 stands for 0.017 inch, which is 0.43 mm. At the same thickness, this corresponds to DURAVOLTA 43.
| Formex | Thickness | DURAVOLTA | UL 94 DURAVOLTA (V-0, VTM-0 for thin films) |
|---|---|---|---|
| GK-5 | 0.005 in = 0.13 mm | DURAVOLTA 12 | VTM-0 (in-house test, UL listing in preparation) |
| GK-10 | 0.010 in = 0.25 mm | DURAVOLTA 25 | VTM-0 |
| GK-17 | 0.017 in = 0.43 mm | DURAVOLTA 43 | V-0 |
| GK-30 | 0.030 in = 0.76 mm | DURAVOLTA 76 | V-0 |
| GK-40 | 0.040 in = 1.02 mm | DURAVOLTA 100 | V-0 |
For GK-5 and GK-10, many people look for a V-0 alternative in 0.13 or 0.25 mm. At these thicknesses, VTM-0 is the relevant UL 94 rating for thin films. What this means is explained on the page UL 94 V-0 for thin films.
DURAVOLTA is halogen-free. Whether a DURAVOLTA type can replace a specific Formex part in your application, 1A STAR will be happy to check on the basis of your drawing or sample.
Formex is a trademark of ITW.
Request DURAVOLTA
Minimum quantity. 1A STAR produces DURAVOLTA parts from one piece. Granules are supplied from 500 kg.
Samples. 1A STAR usually provides samples free of charge, also as a part to your drawing.
Response time. 1A STAR usually answers DURAVOLTA enquiries by the next working day at the latest.
Delivery time. Films and sheets are largely in stock. 1A STAR usually delivers finished parts to drawing within two to three weeks, and at short notice in urgent cases by arrangement.
What your enquiry should include: drawing or dimensions, thickness, required flammability rating, quantity, requested delivery date.
Request DURAVOLTA
Send us your enquiry – we usually reply by the next working day at the latest.
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Frequently asked questions
Who manufactures DURAVOLTA?
DURAVOLTA is manufactured by 1A STAR technische Kunststoffe GmbH in 57399 Kirchhundem, Germany. DURAVOLTA was developed in-house by 1A STAR; the formulation is registered with UL under E354767. Films and sheets are extruded in Germany to this formulation, and in its own plant in Kirchhundem, 1A STAR turns them into die-cut parts, bent parts and self-adhesive parts to drawing. DURAVOLTA is the brand name of this film.
Where is DURAVOLTA processed?
In 1A STAR's own plant in Kirchhundem in the Sauerland region of Germany. This is where finished parts made of DURAVOLTA are produced, from die-cutting, plotting and milling to creasing, bending and laminating. Only injection-moulded and thermoformed parts are produced by a partner company.
Is DURAVOLTA UL 94 V-0 in all thicknesses?
No. DURAVOLTA achieves UL 94 V-0 from a thickness of 0.43 mm up to 1.1 mm. DURAVOLTA 25 at 0.25 mm is rated UL 94 VTM-0, the test method for thin films. DURAVOLTA 12 at 0.125 mm achieves VTM-0 by in-house testing; the UL listing is in preparation. DURAVOLTA 10 and the 2 mm and 3 mm sheets are not yet UL rated, but should pass certification without any problems. If your specification requires V-0, choose DURAVOLTA 43 or thicker.
Is there a DURAVOLTA with UL 94 V-0 in 0.125 mm or 0.25 mm?
At 0.25 mm, DURAVOLTA 25 achieves class VTM-0 according to UL. DURAVOLTA 12 at 0.125 mm achieves VTM-0 by in-house testing; the UL listing is in preparation. VTM-0 is the best class of the test method that UL 94 provides for thin films instead of the V test, in order to obtain a statement comparable to V-0.
Is DURAVOLTA halogen-free?
Yes. DURAVOLTA is halogen-free according to IEC 61249-2-21 and has been since its introduction. There is no halogenated version. DURAVOLTA is also REACH and RoHS compliant.
Since when has DURAVOLTA been listed with UL?
Since 28 October 2014. The File number is E354767, with categories QMFZ2 for the USA and QMFZ8 for Canada. UL monitors the listing continuously; the formulation may not be changed without UL's approval.
Which DURAVOLTA type replaces Formex GK-17?
DURAVOLTA 43. Both are 0.43 mm thick; DURAVOLTA 43 achieves UL 94 V-0 and is halogen-free. GK-10 corresponds to DURAVOLTA 25, GK-30 to DURAVOLTA 76 and GK-40 to DURAVOLTA 100.
Is DURAVOLTA available in black?
No, black DURAVOLTA is not part of the product range. DURAVOLTA is produced in natural / white, and the UL rating applies to this version. Tracking and burn marks are also easier to spot on white material. If your application requires a different colour, please contact 1A STAR.
Is there a minimum order quantity?
No. 1A STAR produces DURAVOLTA parts from one piece. Only granules are supplied from 500 kg. Samples are usually free of charge, also to drawing.
How fast does 1A STAR deliver?
Films and sheets are largely in stock. 1A STAR usually delivers finished parts to drawing in two to three weeks, and at short notice in urgent cases by arrangement. 1A STAR usually answers enquiries by the next working day at the latest.
Is DURAVOLTA available as rolls above 0.43 mm?
Yes, 0.76 mm and 1.00 mm are possible as rolls, but they are not stock items. At these thicknesses the material keeps the curl from the roll, and it usually cannot be removed easily from die-cut parts. For finished parts from 0.76 mm, 1A STAR recommends sheets.
Does 1A STAR also process other insulating materials?
Yes. 1A STAR also produces die-cut and bent parts to drawing from Nomex, Mylar and Kapton.
As of: October 2026