Fischer Toe Warmer

From New Moon:
Just enough to keep the toes warm, no bunching or struggling to get over the entire boot. Tuck a heat pack under the neoprene cover and ski into the arctic temps in comfort. Much more lightweight and easier to use than a full over boot
From the Manufacturer:
The Toe Warmer ensures warm feet during training or on tour, even in very cold conditions. The cross-country overboot for the toe area impresses with its easy handling and, thanks to its small pack size, fits in any bag.