Equipment type
Cordless e-files: battery claims, bit fit, chargers and travel
What makers claim for cordless e-file runtime, speed and bit fit, why battery figures conflict, and what to check about chargers and flying.
Also listed as portable e-file, cordless nail drill, rechargeable nail drill
Short answer
A cordless e-file runs from a rechargeable battery, so you can work away from an outlet. Makers' runtime claims vary and rarely come with a test method: KUPA claims 10-12 hours for the Passport NEXT, while Medicool's 35K Portable page claims up to 20 hours and its own 2025 guide says 8. Check the stated bit shank too, because not every maker publishes it.
Key facts
- What it does
- Rechargeable nail drill: a portable control box or base powers the handpiece[1][2]KUPA's Passport NEXT pairs a portable control box with the Companion handpiece. Young Nails' EF300P ships with a controller, handpiece and charging base.
- Input voltage
- "Automatic switching 110/220 volts" (KUPA Passport system)[3][4]KUPA's statement. A replacement charger's output voltage must match the device's input, and its current must be compatible, according to Health Canada.
- Bit shank
- 3/32 inch (KUPA Passport NEXT, Medicool 35K Portable); not stated by Kiara Sky or Young Nails[1][5][6][2]Kiara Sky's Beyond Pro Portable page and Young Nails' EF300P page do not state a shank size. Ask the maker before buying bits.
- Speed (claimed)
- 30,000 RPM (KUPA Passport NEXT); up to 35,000 RPM (Medicool 35K Portable, Kiara Sky Beyond Pro Portable); 0-35,000 RPM (Young Nails EF300P)[1][5][6][2]Maker figures, not measurements under load.
- Torque published
- 4.8 N-cm (Medicool 35K Portable)[5]Medicool states no test method, so do not compare it with another brand's torque figure as if both were measured the same way.
- Battery (claimed)
- 10-12 hours and a 2-hour full charge (KUPA Passport NEXT); up to 20 hours on Medicool's 35K Portable product page; 10 hours (Kiara Sky Beyond Pro Portable)[1][5][7][6]Medicool's own 2025 guide lists the 35K Portable at 8 hours. None of these makers gives a test method.
- Handpiece size
- KUPA Companion: 4.75 in long, 0.8 in diameter, 5 oz; Medicool 35K Portable: 4.9 oz[1][5]Maker specs.
- Safety marks
- None named on KUPA's Passport pages[3][1][8]Health Canada says replacement chargers should carry a Canadian mark such as CSA, cUL or cETL.
Watch out for
- Battery figures disagree even within one brand. Medicool's 35K Portable product page claims up to 20 hours, while Medicool's own 2025 guide lists the same model at 8 hours.
- Not every maker states the shank. KUPA and Medicool list standard 3/32-inch bits; Kiara Sky's Beyond Pro Portable page does not state a shank size, so ask before buying bits for it.
- Use the original charger. Health Canada recommends the original charger, says a replacement's output voltage must match the device's input, and advises against using swollen, dented or damaged lithium-ion batteries.
- Check the warranty on the product page you buy from. KUPA's Passport NEXT page states one year; a KUPA news post says otherwise, so do not count on a longer term without asking KUPA.
Who it suits: mobile techs and anyone working away from an outlet. If you work at one desk, a corded e-file avoids battery wear. Compare the trade-offs in corded vs cordless nail drills.
Planning to fly or ship one? Read flying with rechargeable nail equipment first.
Questions
How long does a cordless nail drill battery last?
Only the maker's claim is available. KUPA claims 10-12 hours for the Passport NEXT with a 2-hour full charge, Medicool claims up to 20 hours on the 35K Portable product page (its 2025 guide says 8 hours), and Kiara Sky lists a 10-hour battery for its Beyond Pro Portable. None of them states a test method.[1][5][7][6]
Can I take a cordless e-file on a plane?
PHMSA says airline passengers can generally bring lithium-battery devices under FAA conditions and points travelers to the FAA PackSafe guidance. Check current FAA and airline rules for your specific device before you fly.[10]
Do cordless e-files take the same bits as corded ones?
Often, but check. KUPA and Medicool list standard 3/32-inch bits for their portable drills. Kiara Sky's portable drill page does not state a shank size, and Young Nails' EF300P page gives no shank data. See 3/32 vs 2.35 mm bits.[1][5][6][2]