Synthetic Down
Insulation made of polyester fibers engineered to mimic down's warmth and compressibility.
What is Synthetic Down? Insulation made of polyester fibers engineered to mimic down's warmth and compressibility.
Synthetic down (PrimaLoft, Polartec Alpha, Thinsulate, ThermoBall) replicates the warmth-to-weight ratio of natural down using fine polyester fibers. Synthetic down maintains insulation when wet, dries faster, costs less than premium down, and avoids ethical concerns about feather sourcing. It is slightly heavier and less compressible than equivalent natural down.