Pure Mulberry Silk Duvet Insert – Double Cocoon Fill, All-Season | Heartcosy

Not all silk duvets are the same. This one starts with the fill.

Most silk duvets use short-strand or mixed silk that compresses 
over time. This duvet is filled with 100% double cocoon mulberry 
silk — a construction that uses the entire continuous filament 
from two interlocked cocoons, hand-stretched into layers for 
even loft and long-lasting resilience.

The difference you feel on night one, you'll still feel three 
years later.

---

The fill: Double Cocoon Mulberry Silk

100% Mulberry Silk — no synthetic blend, no filler fiber

Double cocoon construction — fibers are longer and more 
interconnected than single-cocoon alternatives, resulting in 
better elasticity and resistance to clumping

Hand-stretched layers — each layer is pulled by hand to 
maintain an even distribution and natural loft

Medium-length fibers — optimal balance of softness and 
structural integrity

---

The shell: Breathable Cotton

Soft, natural cotton shell that allows the silk fill to 
breathe freely. Smooth against skin, durable enough to 
protect the fill over years of use.

---

How silk regulates temperature

Silk's natural fiber structure contains microscopic air pockets 
that allow heat and moisture to move freely. In warm conditions, 
this means excess body heat escapes rather than builds up. In 
cooler conditions, those same air pockets trap warmth close to 
the body.

The result is a duvet that responds to your body — not one that 
forces a fixed temperature.

---

Construction details

· Anchor stitching — keeps fill evenly distributed, 
  prevents shifting after washing
· Silk viewing window — allows you to inspect the fill 
  quality without opening the duvet
· Corner and edge security loops — keeps the insert 
  positioned inside your duvet cover
· Available in multiple fill weights:
  Light (summer) · Mid-weight (spring/fall) · Warm (winter)

---

Care

· Recommended: dry clean or gentle hand wash in cool water
· Do not tumble dry at high heat
· Air dry flat or hang in shade
· Use a duvet cover to protect the silk fill and 
  extend product life
· Do not wring or twist

---

Available sizes: Twin · Full/Queen · King

Select your weight and size above.