Quick answer: The Mulberry Silk Long Johns Thermal Underwear Set For Women is our most-ordered product of 2026: 53 orders and 78 sets since January 1. Each $44.99 set pairs a long-sleeve top with matching bottoms in 100% mulberry silk knit — soft, lightweight, moisture-managing, and slim enough to disappear under everyday outfits. Seven colors, sizes XS–XL.
It is a little funny that the best-selling product at a store called Cmfrt Pants is not, strictly speaking, pants. The Mulberry Silk Long Johns Thermal Underwear Sets For Women have out-ordered every pair of cargos, joggers, and jeans we sell this year. Here is what the set actually is, what the listing promises, and an honest word about buying thermals in July.
No. 1 by real orders, not by hype
Since January 1, 2026, the store has logged 467 orders. This thermal set appears in 53 of them — 78 sets sold — making it the only product in the store to clear 50 orders this year. Second place, the Zipper Straight Leg Pants, sits 14 orders behind.
What a mulberry silk thermal set actually is
Each set is a long-sleeve top and matching bottoms, knit from a listed 100% mulberry silk in a fine gauge. The listing's pitch is a base layer that works by staying out of the way: the knit traps comfortable warmth while remaining light, the silk helps manage moisture during active moments, and the close-cut outline adds minimal bulk under jeans, sweaters, and outerwear. The stretch is listed as moderate four-way flexibility — enough to move with you through a commute or a day of errands — and the interior is finished for a smoother feel against the skin.
How to layer it (straight from the listing)
The listing suggests a simple three-part system for winter days: start with this silk set as the base, add a midweight knit when the forecast dips, and finish with an insulated shell for wind and snow. Because the outline is slim, each layer sits cleanly over the last — warmth builds without the marshmallow effect, and seams stay smooth under sweaters and denim.
Where it earns its keep
The listing names these use cases:
- City commutes in cold seasons
- Skiing base layers for resort trips
- Air-conditioned flights and long travel days
- Mountain cabins and weekend getaways
- Daily layering for office or errands
- Evening strolls in cool climates
An honest note about buying thermals in July
We will not pretend mid-July is peak long-johns weather. Two honest reasons this guide exists now. First, the listing itself is not strictly a winter pitch: it calls out air-conditioned flights and long travel days, and describes the set as useful in fall, winter, and cool spring nights — a longer season than the name suggests. Second, the order data is what it is: this set has out-ordered everything else in the store since January. If you already know cold weather is coming, buying ahead of the cold season just means the set is in your drawer before the first frost.
Specs at a glance
| Price | $44.99 |
|---|---|
| Set contents | Long-sleeve top and matching bottoms |
| Fabric | 100% mulberry silk knit (as listed) |
| Feel | Ultra-soft, smooth surface |
| Stretch | Moderate four-way flexibility |
| Fit | Close outline for clean layering |
| Weight | Lightweight thermal gauge |
| Colors | Black, Khaki, Beige, Light Pink, Gray, Red, Dark Pink |
| Sizes | XS–XL |
| Care | Machine wash gentle; air dry |
Frequently asked questions
What are the mulberry silk long johns made of?
The listed fabric is 100% mulberry silk knit in a fine gauge. It has an ultra-soft, smooth feel, helps manage moisture, and offers moderate four-way stretch for easy movement.
What comes in the set?
Each set includes a long-sleeve top and matching bottoms. Both pieces are cut close to the body so they layer cleanly under sweaters, jeans, and outerwear.
Will they feel bulky under everyday clothes?
Minimal bulk is the point. The set is a lightweight thermal gauge with a close outline, designed to sit neatly under jeans, office wear, and winter layers.
How do I care for mulberry silk thermals?
Machine wash on a gentle cycle and air dry. The interior is finished for a smoother feel, and the seams are fine and tidy so they stay comfortable under other layers.
Why would I buy thermals in July?
Two honest reasons: the listing names air-conditioned flights and long travel days as a use case, and buying ahead of the cold season means the set is ready for fall. It has been our most-ordered product since January, at 53 orders.
More guides from Cmfrt Pants
- Our best-selling pants of 2026 — ranked by real orders
- Men’s High Stretch Multi Pocket Cargo Pants — fit, fabric & sizing guide
- Women’s lightweight cargo capri hiking pants — the full guide
- How to choose cargo pants — fit, fabric & pockets
Order counts cover January 1 through mid-July 2026. Prices, options, and fabric details come from the product listing, are current as of publication, and may change; see the product page for the latest details.