1. Assess natural lash strength before choosing this diameter over 0.15.
2. Cleanse and prime, then tape and map with conservative lengths.
3. Lift each lash from the strip at the base rather than mid-fibre.
4. Isolate a single natural lash cleanly.
5. Dip the base into a fresh glue dot without creating a visible bead.
6. Align 1-2mm of the extension base along the natural lash and hold until it grabs.
7. Keep the longest lengths for the strongest lashes only.
8. Comb through, check for stickies, and cure fully.

• Upgrading diameter and length together - a client moving from 0.15 to 0.18 who also gains 2mm is taking a much larger step than she realises.
• Using it on average-to-fine lashes - the additional weight over 0.15 is meaningful, and marginal lashes shed.
• Over-loading adhesive - a bead is more visible on a thicker fibre.
• Assuming the client will notice a dramatic difference - the step from 0.15 is visible but not transformative; pair it with a curl or map change if she wants more.
• Ignoring L curl - a thick extension sitting at the wrong angle is far more obvious than a fine one.

CHOOSING BETWEEN 0.15, 0.18 AND 0.20

• Finish - 0.15: Defined and natural | 0.18: Clearly defined | 0.20: Bold and structural
• Weight per lash - 0.15: Standard classic | 0.18: Noticeably heavier | 0.20: Heaviest in classic use
• Natural lash requirement - 0.15: Healthy average lashes | 0.18: Strong lashes | 0.20: Very strong lashes only
• Client brief - 0.15: Enhanced but natural | 0.18: Visibly done | 0.20: Maximum classic impact
• Length flexibility - 0.15: Full range usable | 0.18: Keep conservative | 0.20: Keep short
• Curl options - 0.15: Seven curls | 0.18: Four curls | 0.20: Four curls

Materials: Super Mink PBT fibre on a 2mm easy-peel adhesive strip with foil backing. Formaldehyde-free, latex-free, vegan and cruelty-free. Patch test new clients for adhesive sensitivity.

Is the step from 0.15 to 0.18 visible to a client?

Side by side, yes - the lash line reads more defined and the set photographs more strongly. On its own it is an incremental rather than dramatic change, so if a client wants an obvious difference, combining the diameter step with a curl or map adjustment gives a better result.

Which clients should not have 0.18?

Anyone with visibly fine natural lashes, anyone recovering from lash damage, and clients with a fast natural shed cycle where the additional weight compounds normal loss. On those clients, holding 0.15 and adjusting curl and map achieves more than adding diameter.

Does 0.18 need a shorter infill cycle?

Usually slightly, because heavier extensions shed more visibly and stress the base more as the lash grows out. Two to three weeks is a sensible default rather than three to four.

Can I mix 0.18 with 0.15 in one set?

Yes, and it is often the better approach on an uneven lash line - 0.18 on the strong central lashes for definition and 0.15 through the inner and outer sections where lashes are finer. The visual difference between the two is small enough that the transition is invisible.

Why do my 0.18 sets lift at the outer corner specifically?

The outer lashes are frequently the finest and shortest in the line, and they carry the longest extensions in most maps - so weight and leverage both peak there. Shortening through the outer third or dropping to 0.15 in that zone usually resolves it.