What hair-stroke brows are
Hair-stroke brows are drawn with an electric PMU pen that implants pigment along the natural direction of eyebrow growth, one fine line at a time. Manual microblading chases the same look with a hand-held blade. The goal is identical; the tools are not.
For a client, that difference lands in two places: whether the lines hold, and whether the skin shows it afterwards. A clinical review of cosmetic tattooing records that fibrosis and scarring are seen especially after microblading. Both routes traumatise skin, so the question worth asking is how the practitioner keeps depth and intensity under control.
Depth is the whole conversation
Pigment only stays if it goes below the epidermis, which renews continuously and carries away anything left on top of it. A study of tattoo and PMU colourants measured cosmetic pigment around the epidermal–superficial dermal junction — roughly 0.3–0.5 mm — and ECHA explains why tattoo ink has to reach the dermis to last.
So the question worth asking is not "how fine can you draw" but "how do you judge that you have reached depth".
How a machine builds a stroke
The machine route consumes cartridges. On needle geometry, ATTO's 1R single needles run across eight diameters from 0.16 mm up to 0.50 mm, alongside RL, RS, Flat, MG, CM, XF and 0411U groupings. These are the option values recorded on the product pages.
The consumable on the manual route is the blade: ATTO lists microblading needles at 0.18 mm and 0.25 mm across configurations from 7CF to 18U. Both routes publish their options in the product record, so the two can be compared field by field.
A full item-by-item comparison of the two routes is in Microblading versus machine PMU.
The interface comes before the needles
ATTO's PMU cartridges come in two connections — universal-style and BMX screw — and they do not interchange. Choosing a machine means choosing an interface ecosystem, and that decision precedes buying needles. Connection, configuration, diameter and taper, and pack size are all fields in the product record, set out step by step in the PMU cartridge selection guide.
Browse ATTO PMU cartridges by interface and configuration
For brows, ATTO lists a powder pigment line in seven shades (Sandy Brown, Latte Brown, Light Brown, Amber Brown, Espresso Brown, Toffee Brown, Black Brown), ATTO also lists a separate powder line shared by eyeliner and scalp work, with two shades. Shade names describe colour, not how long a result stays.
Four things to confirm before booking
1. The examples you are shown are healed. Ask for finished, healed work, ideally on skin close to your own. Same-day photographs show lighting and contrast, not the outcome.
2. The instruments are single-use and opened in front of you. The FDA states that unsterile tattooing equipment and needles can transmit infectious disease, including HIV and hepatitis. The CDC advises that instruments and materials intended to penetrate the skin, ink included, be used once and disposed of, or cleaned and sterilised before reuse. Watching the packaging being opened is a normal request.
3. The pigment's documentation is available. The FDA notes that no colour additive is approved for injection into the skin, and that some pigments in tattoo ink are not approved for skin contact at all. In the EU, REACH has restricted thousands of hazardous substances in tattoo and PMU inks since 2022 and requires the label to state intended use, batch reference and ingredients. Asking for the product data sheet is reasonable.
4. A correction plan exists. Cosmetic pigment changes over time; fading and colour shift are both documented late-onset outcomes. The conversation should cover when you come back for assessment and which shades would be used, instead of a promise about duration.
If you want to practise the technique
ATTO's practice range is organised by purpose: an A4 silicone skin made for hair-stroke work, a 3D eyebrow PMU practice skin, and modules in light, medium and dark tones. Practice material is silicone, not skin tissue.
Browse eyebrow and facial practice material
The bottom line
For the machine route, start with the fields you can verify — interface, configuration and pigment documentation — then ask the practitioner how depth is judged and how correction is planned. Suitability does not come from needle diameter alone.