“ Single audible pockets on each side
https://skydivingwin.gitbook.io/untitled/page/skydiving-understanding-age-requirements
Indoor skydivers use different body positions to move and stay afloat. For example, with straight arms and legs, they create a large surface area to get lifted up by the wind. On the contrary, by tucking in their legs and arms, they decrease this area, which lets them descend through the slope. ”