Can affect the rider's pelvis tilt, refines the twist, and slightly deepens the seat. It goes under the front of the seat, with the wide side toward the pommel and the pointy side toward the rider. It can be moved forward/back for a greater effect.
Riders who have a low pelvic floor may not like the bolster. For those who are looking at the product to tilt the pelvis, one of the other rider balancing aids will have a great effect without discomfort.
To install, release the velcro under the front center of the seat, then tug the seat back over the front dees. Place the bolster and press the seat back into position, making sure all is still symmetrical. Replace the front velcro tab and push the seat back over the front dees. This last part can be difficult, especially when the saddle is new - to make it easier, pull some twine or a shoelace through the dee to give you more leverage.