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This page describes products and general use; it is not medical advice.
TENS pads (also called TENS electrode pads, TENS unit pads or tens machine pads) are the adhesive electrodes that carry current from a TENS unit to the skin. Clinic staff, buyers and students use this page to see what a pad is made of, how it is classified by FDA separately from the unit, and what “reusable” actually means on the label.
What are TENS pads?
A TENS pad is a cutaneous electrode: under 21 CFR 882.1320, which identifies it as an electrode applied directly to a patient’s skin, either to record physiological signals or to deliver electrical stimulation. The unit itself is defined separately in 21 CFR 882.5890 as a device “used to apply an electrical current to electrodes on a patient’s skin to treat pain.” Both regulations list Class II (performance standards). For how the unit works, see what a TENS unit is and how a TENS unit works; this page covers the pad as a product.
Who uses them: FDA 510(k) K241512 describes its pad as used in home or clinical settings by patients or clinicians.
What is a TENS electrode?
“TENS electrode” and “TENS pad” name the same product category. FDA does not use a separate TENS electrode regulation: the cutaneous electrode in 21 CFR 882.1320 covers electrodes that either record signals or deliver stimulation, and 510(k) summaries for TENS electrodes are filed under this regulation with product code GXY (K161282, K241512). In those summaries the electrode is described as passive: it carries the signal from the stimulator, through the lead wire or snap button, to the user’s skin (K161282). The summaries name the stimulators they work with as TENS or EMS units (K161282, K241512).
The electrode takes more than one physical form. The pads in K161282 and K241512 are self-adhering hydrogel pads, while the wrap accessory electrodes in K240108 are made of conductive silicone rubber and are shaped for body areas such as the wrist, knee or foot. All three are cleared under the same regulation (21 CFR 882.1320, Class II).
How a TENS pad is built
FDA 510(k) K241512 (“Electrode Pad”, decision date 2025-01-15, product code GXY, regulation 21 CFR 882.1320) describes a pad as an accessory to a TENS or EMS unit that transmits current to the skin. That submission lists these parts:
- top cover
- connector: snap button or lead wire
- conductive carbon film
- conductive hydrogel
- carrier liner made of PET (polyethylene terephthalate), the backing the pad is peeled from
This is one manufacturer’s submission, not a standard for every pad on the market.
Types and variants of TENS pads
| Variant | What FDA 510(k) K241512 states | Key difference |
|---|---|---|
| Snap-button pad | Current is received through a snap button (K241512) | Connects to a lead that snaps onto the pad |
| Lead-wire pad | Current is received through a lead wire (K241512) | Wire is attached to the pad itself |
| Rectangular pad | Example size 50 x 100 mm (K241512) | Longer contact area |
| Square pad | Example size 50 x 50 mm (K241512) | Compact contact area |
The submission lists rectangle and square shapes in various sizes; the two dimensions above are examples from that document, not a standard size range.
Are TENS pads reusable?
Pads described as reusable are, in the labeling of K241512, non-sterile and intended for single adult patient multiple application use. That wording means one person may apply the same pad more than once; it does not mean a pad is shared between patients. The submission does not state a number of uses, so follow the manufacturer’s instructions for use (IFU) for the specific pad.
Reusable pads and electrodes in FDA 510(k) summaries
| Submission | Device | What the document states about reuse |
|---|---|---|
| K161282 (letter dated 2016-10-30) | FlexStim Neurostimulation Electrodes, snap and lead-wire versions | Indicated as “reusable, self-adhering”; the electrodes are “designed for single patient/multiple application use”; not a sterile product; patient-contacting material is conductive hydrogel; labeled for over-the-counter use; environments of use are healthcare facility and home |
| K240108 (letter dated 2024-06-10) | Wrap Accessory Electrodes made of conductive silicone rubber | Labeled for over-the-counter use with legally marketed TENS or powered muscle stimulators; its predicate is described as non-sterile, reusable and intended for adult patients |
| K241512 (decision 2025-01-15) | Electrode Pad | Non-sterile, single adult patient, multiple application use; number of uses not stated |
None of these documents gives a number of uses, a cleaning method or a replacement interval, so the pad’s own labeling and IFU are the only place those details can come from. “Reusable” in these summaries is a labeling category (non-sterile, single patient, multiple application), not a performance guarantee.
How to choose: what the labeling and regulations state
- Match the connector. A snap-button pad needs a unit lead that snaps on; a lead-wire pad connects by its wire (K241512).
- Read the labeling for patient scope. The K241512 pad is labeled for a single adult patient with multiple applications and is non-sterile (K241512).
- Check that the pad is intended for use with your type of unit: the K241512 pad is an accessory to TENS or EMS units. See TENS vs EMS for how the two unit types differ.
Safe use and handling basics
Pads are applied directly to the skin, so the manufacturer’s labeling and IFU for the specific pad and unit govern its handling and storage. The K241512 pad is non-sterile and is labeled for a single adult patient, so a pad is not passed between people. For other devices that use skin-contact electrical output, compare iontophoresis.
Common mistakes
- Treating the pad and the unit as one regulated device. They carry separate FDA identifications (882.1320 and 882.5890), although both are Class II.
- Reading “reusable” as “shareable”. The labeling in K241512 is single patient, multiple application.
- Assuming a pad is sterile. The K241512 pad is non-sterile.
- Assuming one standard pad size. K241512 lists rectangle and square pads in various sizes.
FAQ
What are TENS unit electrode pads made of?
In FDA 510(k) K241512: a top cover, a snap button or lead wire connector, conductive carbon film, conductive hydrogel and a PET carrier liner.
Are TENS pads reusable?
A pad labeled as in K241512 is for a single adult patient and multiple applications, and it is non-sterile. The number of uses depends on the manufacturer’s IFU.
Does FDA regulate TENS pads separately from the machine?
Yes. The pad falls under cutaneous electrodes (21 CFR 882.1320, Class II); the stimulator falls under 21 CFR 882.5890 (Class II).
Is a TENS electrode the same as a TENS pad?
Yes. Both terms describe the cutaneous electrode (21 CFR 882.1320) that connects a TENS or EMS unit to the skin. Forms differ: hydrogel pads with a snap button or lead wire (K161282, K241512) and conductive silicone rubber wraps (K240108).
What does “reusable” mean on a TENS pad label?
In K161282 and K241512 it means non-sterile and intended for a single patient across multiple applications. The summaries do not state a number of uses; the manufacturer’s IFU does.
Sources
- eCFR, 21 CFR 882.1320 Cutaneous electrode: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-882/subpart-B/section-882.1320, checked 2026-10-30.
- eCFR, 21 CFR 882.5890 Transcutaneous electrical nerve stimulator for pain relief: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-882/subpart-F/section-882.5890, checked 2026-10-30.
- FDA 510(k) K241512, Electrode Pad, Shenzhen Deliduo Medical Technology Co., Ltd.: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K241512; summary text checked 2026-10-30 at https://fda.innolitics.com/device/K241512.
- FDA 510(k) K161282, FlexStim Neurostimulation Electrodes, Medico Electrodes International Ltd.: https://www.accessdata.fda.gov/cdrh_docs/pdf16/K161282.pdf, checked 2026-10-31.
- FDA 510(k) K240108, Wrap Accessory Electrodes, Gymmax Technology Shenzhen Co., Ltd.: https://www.accessdata.fda.gov/cdrh_docs/pdf24/K240108.pdf, checked 2026-10-31.
