What were ski boots used for in space?

Answer 1

I think you mean what are moon boots used for with skiing. NASA worked with Raichle to make the moon boots which after being used in space was adapted into skiing.

From NASA.gov

In cooperation with Raichle Molitor USA Inc. and the international Raichle organization, Comfort Products developed the Raichle Flexon concept in ski boots. The Flexon concept is an adaptation of the Accordion-like corrugations of extravehicular space suit joints, which allows ski boots to flex without significant distortion. The design provides immediate transmission of power and therefore precision skiing. Comfort Products also applied heating element circuitry from Apollo astronaut's clothing to foot-warming devices in their boots in the 1970s.