Bondage straight jackets restrain the wearer so that arm use is completely rendered useless. Straight jackets are used in BDSM practices where a dominant will restrain a submissive. Restrain in this manner is consentual and provides sexual stimulation for both participants. Fetish sleep sacks are similar to sleeping bags in that they can be zipped up after an individual enters inside. Sleep sacks differ in that the head protrudes out of the sack and the sack is typically fastened to the neck with a collar. This completely restrains the individual in a comfortable way. This method is good to use when restraining for an extended period of time and comfort is a consideration.