Everything Yoga Pranayama Cotton Yoga Bolster Our cotton pranayama bolsters provide perfect support for many yoga postures. Designed to support the length of the spine, this bolster facilitates gentle expansion of the lungs to facilitate deeper breathing. You will find that this bolster is firm enough to provide full support, yet soft enough to be quite comfortable. The bolsters are stuffed with 100% cotton batting. The bolsters are 25'' long by 3'' high by 6'' wide.