Cold days bring the best climbing conditions—and the Thorium Jacket lets you make the most of them| Designed for durability, this belay jacket features bold baffling stuffed with 750-fill down for reliable warmth, while the rugged mini-ripstop shell withstands sharp rock| Climbing-specific details like a two-way front zip for harness access and oversized internal dump pockets to keep shoes warm between burns make it an essential layer for the chilliest sessions