Micron is the diameter of each wool fibre. The smaller the number, the finer and softer the wool. Average human hair is about 100 µm; everyday wool is around 30 µm, which can feel scratchy. Merino wool is already much finer (often 18‑22 µm), but superfine merino like Lasting’s 16.5 µm yarn is in a league of its own . Those fibres are roughly 0.016 mm across—so soft that people who normally “itch” from wool can comfortably wear it .
Why superfine merino feels amazing
Silky‑soft & non‑itchy – With a diameter of just 16.5 µm, superfine merino wool feels smooth like silk . It doesn’t prick or itch, which is why it’s often chosen for next‑to‑skin garments like base layers and tees.
Built‑in climate control – Each fibre has a hydrophobic surface that repels sweat, while the hydrophilic core absorbs up to 30 % of its weight in moisture . This keeps the fabric dry to the touch and allows it to cool you in heat and insulate you in the cold .
Natural odour control – Merino is composed of keratin proteins that bind to bacteria and limit their growth . Clothes made from it stay fresh even after multiple wears.
Breathable & thermoregulating – Its irregular, flaky surface creates tiny air pockets for insulation and airflow . Even under layers, the fabric remains breathable and resists clamminess .
Hypoallergenic & UV‑resistant – Medical literature shows no true allergy to wool; people simply feel discomfort from coarser fibres. Superfine 16.5 µm wool is comfortable even for sensitive skin . It also blocks UV rays and is more fire‑resistant than synthetics .
Inspiring products made from 16.5 µm merino
Product
Key details
Price (approx.)
Lasting Woolsens 160 g base layer (superfine 16.5 µm merino)
This Czech‑made base layer uses 100 % mulesing‑free 16.5 µm yarn. The light 160 g knit is ideal next to skin and excels at moisture elimination, thermoregulation and comfort . A heavier 260 g double‑face version works as a mid‑layer for freezing conditions .
~US$ 50–70 depending on style (varies by retailer).
Outlier Ultrafine Merino Cut One T‑Shirt
A near‑perfect tee made with 100 % pure, top‑capped 16.5 µm merino from New Zealand . Outlier notes that they moved from 17.5 µm yarn to 16.5 µm to make the fabric even softer . The hygroscopic fibres keep you cool in heat and warm in cold . The 190 gsm knit is durable yet soft, and the ethical NZFAP‑traceable merino is non‑mulesed .
US$ 150
Other uses
16.5 µm merino is commonly found in high‑end dress shirts, suits and sport jerseys, as well as lightweight hoodies, leggings, underwear and base layers for hiking, skiing and running. Because it remains odour‑free, you can wear it on long trips without constant washing.
How to choose & care for superfine merino
Check weight (GSM) – Lighter fabrics (150–160 g/m²) work well as base layers or summer tees, while mid‑weights (190–260 g/m²) are ideal for all‑season shirts and mid‑layers.
Look for certifications – Labels like NZFAP and RWS guarantee animal welfare and traceability . Mulesing‑free yarn (as used by Lasting) ensures sheep were not subjected to painful procedures .
Care tips – Wash in cold or warm water with mild detergent; air‑dry or tumble on low. Expect slight shrinkage when first washed .
Final thoughts
If you crave luxurious comfort with performance superpowers, 16.5 µm merino wool is the way to go. Its silky softness, natural temperature regulation, odour resistance and sustainability make it ideal for everything from athletic base layers to everyday T‑shirts. This ultrafine fibre takes the already incredible merino wool to an inspiring new level—so treat yourself to a piece and feel the difference!