# YSHIELD M2L magnetic shielding film

> Two-layer 0.12 mm magnetic shielding film declared at 12.1 dB single layer rising to 21.7 dB in four layers, quoted by the manufacturer as a field-amplitude reduction of 75.1% to 91.8%.

- Canonical URL: https://emfbase.com/materials/yshield-m2l
- Collection: Shielding products
- Record id: `materials:yshield-m2l`
- Status: verified
- Last verified: 2026-08-12
- JSON: https://emfbase.com/api/materials/yshield-m2l
- Also known as: M2L, magnetic shielding film, mu-metal film

## Key values

- **Manufacturer:** YSHIELD GmbH & Co. KG
- **Model:** M2L
- **Material class:** High-permeability alloy (mu-metal) magnetic shielding
- **Fields addressed:** elf magnetic
- **Grounding required:** No
- **Thickness:** 0.12 mm

## Declared attenuation

Each figure is the manufacturer's declaration for the frequency and the layer or coat count named next to it. The percentage is computed from the dB value, not quoted separately.

- **power frequency (50/60 Hz) magnetic field, single layer** — 12.1 dB — removes 75.2% of the field amplitude
- **power frequency (50/60 Hz) magnetic field, two layers** — 16.3 dB — removes 84.7% of the field amplitude
- **power frequency (50/60 Hz) magnetic field, three layers** — 19.5 dB — removes 89.4% of the field amplitude
- **power frequency (50/60 Hz) magnetic field, four layers** — 21.7 dB — removes 91.8% of the field amplitude

## Test method

Manufacturer-declared magnetic-field attenuation per layer count, quoted with the corresponding percentage reduction in field amplitude. These are amplitude ratios, not the power ratios used for the same manufacturer's RF products.

## Construction

Two-layer high-permeability alloy film protected with laminating foil on both sides, 21 cm wide.

## Typical application

- Local shielding of a transformer, riser or supply cable
- Intermediate layer in a wall, floor or ceiling build-up
- Shielding a bed head from a known magnetic source

## What the figure does not cover

- Magnetic shielding works by diverting flux, so a flat film only helps where it sits between the source and the person; it does not enclose a room
- 12.1 dB is a factor of about four in field, not the thousandfold reduction RF materials are quoted at — magnetic fields at power frequency are the hardest case in shielding
- High-permeability alloys lose permeability if kinked, folded, hammered or drilled, and the loss is permanent and invisible
- Declared per flat layer in the manufacturer's fixture: geometry, distance and source orientation change the installed result more than layer count does
- Nothing here addresses RF; the field type is different and so is the material

## What these figures are

Every attenuation value on this page is the manufacturer's own declaration for a flat sample in a test fixture, reproduced so that products can be compared on the same terms. It is not a regulatory limit, not an independent test, and not a prediction of what a meter will read after installation — an installed shield is set by its weakest path, so the only figure that describes a room is a before-and-after measurement of that room.

## Related records

- [High-permeability alloy (mu-metal) magnetic shielding](https://emfbase.com/shielding/high-permeability-alloy): The only material class that meaningfully attenuates power-frequency magnetic fields, and even then typically by a factor of two to five in a retrofit — which is why distance and source correction are preferred.
- [Shielding attenuation](https://emfbase.com/quantities/shielding-attenuation): Decibels of field reduction provided by a material. Every 10 dB is a factor of 10 in power density: 30 dB removes 99.9%, 10 dB removes 90%.
- [Magnetic flux density](https://emfbase.com/quantities/magnetic-flux-density): The quantity an ELF gaussmeter reports, expressed in milligauss or microtesla, used to assess wiring, transformers and power lines. 1 µT = 10 mG.

## Sources

- `yshield-product-overview` YSHIELD GmbH & Co. KG (2026). *YSHIELD product overview with technical data and shielding attenuation*. https://www.yshield.de/pdf/YSHIELD-Produktuebersicht-Productoverview.pdf — manufacturer, link checked 2026-08-12

Data licence: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Dataset version 2026.08.1. Retrieved from EMFBase, https://emfbase.com.

This record is reference data, not medical or legal advice. Regulatory limits, scientific guidelines and precautionary values are labelled separately and answer different questions.