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Outdoor Research says:
For those coldest of cold days, the Spitsbergen Hat is made of 100% lambswool with a wind-blocking WINDSTOPPER® lined earband to keep you warm.
By placing quality first, we can offer the finest guarantee in the industry for each and every product – the Outdoor Research Infinite Guarantee™. We believe so strongly in the quality of the apparel and gear we make that if our product fails to meet your needs at any time, we are happy to replace it. Our products are guaranteed forever.