1) Physical restraint 
Sleepsack or sleep sack can refer to: ...[BDSM] Sleepsacks are a popular type of bondage (BDSM) gear. Sleepsacks are primarily used to confine a person comfortably for an extended period of time. Similar to a conventional sleeping bag, a person climbs into a sleepsack and is usually zipped into it up to their neck. Generally sleepsacks are very tight on the body, adding to the bon...