Keratin Hair Extensions by Bond Type

A client sits down wanting length that survives a high ponytail, a gym session and a week of not thinking about their hair. Clip-ins won't do that, and tape-ins tend to show once the hair goes up. That's usually when the conversation turns to keratin, and the next question is which bond. Choosing keratin hair extensions by bond type decides how long the install takes, how the hair sits against the scalp and what the client feels when they lie down at night.

Why Salons Still Book Keratin Bond Installs

Keratin bond extensions attach strand by strand, in small sections, so there's no weft line or tab edge to hide. Hair falls from each bond roughly the way it grows from the scalp. That's what clients pay for: they can wear it up, part it anywhere and run their fingers through it without hitting a ridge.

The trade-off sits on the stylist's side. A full install is long chair time. It takes a practised hand to keep bonds even and sections clean, and a rushed job shows up weeks later as matting near the root or uneven tension across the head. We'd tell any salon adding the service the same thing: the hair matters, but bond technique matters just as much.

Salons still deciding between keratin, tape, clip-in and weft can compare the methods in our guide to types of hair extensions.

Hot Fusion vs Cold Fusion: How Keratin Tips Attach

Every format in this family arrives with a keratin tip at the top of the strand. What changes is how that tip is fixed to the client's hair.

Hot fusion uses a heated tool to soften the keratin, which the stylist then rolls or presses around a small section of natural hair. As it cools, it sets into a firm bond. U-tip, V-tip and flat-tip all work this way, and they're what most stylists mean when they talk about fusion hair extensions. The bond stays put until it's softened with remover and broken down at the next removal.

Cold fusion keeps heat away from the client. I-tip and nano-tip strands have a hardened keratin tip that slides into a small metal ring together with a section of natural hair, and pliers close the ring. The keratin holds the strand together at the top; it isn't melted onto anything. Calling these "fusion" confuses clients, so we'd keep the two groups apart on your service menu and price list.

Which group to lead with often comes down to who walks through the door. A salon whose clients are nervous about heat near the scalp will book more I-tip. A stylist who wants the flattest finish and is confident with a fusion iron will lean towards flat-tip or V-tip.

Keratin Bond Types Side by Side

Five bond shapes cover most of what salons order. Use the table as a quick reference, then read the detail for the ones you're considering.

U-Tip (Nail Tip)

The classic. The keratin forms a curved cap shaped like a fingernail, and between the stylist's fingers it rolls into a neat cylinder around the section. It's forgiving to learn on and gives a secure hold on medium to thick hair. On fine hair, though, a rolled bond can feel like a small bead at the root, and clients do notice it when they brush. Plenty of fusion stylists trained on this shape and still prefer it, which is why we keep a U-tip range alongside the flatter bonds.

V-Tip

A narrower, pointed bond that tucks closer to the scalp than a U-tip. Stylists like it around the parting and crown, where a bulkier bond would catch the light when the client flips their hair to the other side. Few salons install a full head of V-tip. Many keep a few packs for the visible zones.

Flat-Tip

Here the keratin is pressed into a thin, flat rectangle. It lies against the head, so clients feel it less when they sleep on it or tie their hair back. Run a thumb over an installed flat-tip and you meet a smooth edge with no bump.

Our Flat-Tip Keratin is straight, 16–30 inch, 100g and Double Drawn, in three shades: flat-tip in #12.0, #7.1/12.0 and #7.3/12.0. The two mixed shades give stylists a blended option for clients who don't sit neatly in one colour.

I-Tip (Stick Tip)

A straight keratin stick at the end of the strand, fitted cold with a micro ring. No heat, no glue. The big advantage at the chair is adjustment: at a maintenance visit the stylist opens the ring, slides the strand back up towards the scalp and closes it again.

Ring placement is the thing to watch. Too close to the scalp and the client feels a pinch every time they lie down; too far and the strand swings and tangles. We stock I-Tip Keratin #60, straight, 16–30 inch, 100g, Double Drawn.

Nano-Tip

The smallest keratin tip, closed into a tiny ring that's easy to drop on the salon floor. Once it's in, it's hard to spot even at the hairline, which is why stylists reach for it on clients with fine hair around the face. It's also slow and fiddly to install, and each small ring carries less hair. We've compared it with the other light methods in our guide to extensions for fine hair, and the format has its own nano-tip bonds page.

Matching the Bond to the Client's Hair

Start with the client's own hair. What's in the drawer comes second.

Fine hair needs the lightest bond that will still hold: nano-tip, or small flat-tip bonds placed with care. A heavy rolled bond on thin strands pulls at the root, and the client feels that tug every time they brush or tie their hair up. Thick, coarse hair handles U-tip well, because the rolled keratin grips a fuller section. Clients who wear their hair up most days tend to be happier with flat-tip or V-tip around the hairline and crown, where a bond that stands proud would show.

Then there are clients who simply won't have heat near their head. Give them I-tip, and point out that the ring can be moved up at each visit.

Most fusion stylists have met this one. A client with fine hair arrives wearing large U-tip bonds fitted elsewhere. From across the room it looks good, but the roots are sore and the bonds sit like beads under your fingers. After removal, smaller bonds and a lighter install usually settle it. The hair wasn't the problem; the bond size was.

If a client mentions scalp pain, redness or a lot of hair coming away at the root, stop and suggest they see a dermatologist before anything is reinstalled.

What a Good Keratin Bond Feels Like in Your Hand

Open a sample pack and pick up a small bunch of strands by the tips. Good bonds are all close to the same size and shape. If a few are fat and a few are thin, the install will look patchy and the stylist will spend chair time compensating.

Press a bond between finger and thumb. It should feel firm and smooth, with no cracks, crumbling edges or chalky dust left on your fingertips. Keratin that feels tacky at room temperature is a bad sign too, since it can soften and slip in a warm salon.

Now look where the hair leaves the bond. Every strand should be locked in, with no loose hairs poking out of the top and nothing sliding when you give the strand a gentle tug. Loose hairs at the bond tend to turn into shedding later, and clients usually spot that on their pillow before anyone else does.

Finally, hold a strand up to the light and compare the bottom with the top. Double Drawn hair keeps its thickness much further down the length. With heavily tapered hair the install can look full at the root and wispy by the shoulders, which is hard to fix with more strands.

One more trade situation worth planning for: the sample was lovely, then the bulk order arrives with bonds in two slightly different sizes because it came from separate production runs. Ask your supplier whether repeat orders are made to the same bond spec, and check the first box against your sample before booking clients in.

Removal, Reuse and What Clients Ask

Clients ask two things. Will removal hurt, and can I keep the hair?

Hot fusion bonds come out with a bond remover that softens the keratin and pliers that crush it so the strand slides free. Done patiently, it's mostly a matter of time in the chair; rushing is where breakage happens. Good-quality hair can often be re-tipped with fresh keratin and fitted again, but how well it survives depends on how it was cared for and how long it was worn. We'd never promise a client a set number of reuses.

Cold fusion is simpler to undo. Open the ring, slide the strand out, and if the hair is still in good condition it can go back in with a new ring. That flexibility is a big part of why some clients prefer I-tip, especially those who like to change length between seasons.

Time between maintenance visits varies with how fast the client's hair grows, how oily their scalp is and how they wash. Give each client an estimate for their own hair after the first appointment. A fixed figure on day one is a promise you can't control.

Buying Keratin Hair Extensions Wholesale

Most salons and shops don't need all five formats on day one. For keratin hair extensions wholesale, we'd start with one hot fusion type and one cold type, usually flat-tip or U-tip plus I-tip, in the shades your clients actually wear. Add V-tip or nano-tip once your stylists start asking for them.

Before a bigger order, run the sample through a short check:

• Bond size and shape across several strands, not just the top one in the pack

• Hair direction: smooth when you stroke down, a little resistance when you stroke up

• Thickness at the ends compared with the top of the strand

• Colour against your own ring or a client's hair, in daylight

• Whether reorders are made to the same bond spec and shade

Some buyers would rather make their own tips or run a private label. For them the starting point is loose bulk hair, where you choose the keratin, the tip shape and the strand weight yourself.

Ordering Keratin Bond Samples From Dobi Hair

We've made hair extensions in Vietnam for 15 years, and keratin-tipped strands are one part of that range. Flat-tip and I-tip are the two keratin lines with listed shades today. For U-tip, V-tip and nano-tip, check the category pages for what's currently available.

The most useful next step is a sample in the exact shade and length you plan to stock. Order it from our flat-tip extensions page or the I-tip page above, then put it through the checks in this guide: squeeze the bonds, tug the strands, wash it once and look at the ends. Tell us the bond type, shade, length and rough quantity you have in mind, and we'll quote against that spec.