This bag stabilizer was made to place under your rear bag to provide additional stability. The doughnut shape bag fits underneath Protektor Model or Bald Eagle rear bags. Some rear bags tend to rock due to the rounding they get with use, and the bag stabilizer prevents the rocking. The bag stabilizer also raises the rear bag for those shooting stocks with a near straight comb such as a Borden, TMBR, or Scoville stock. Legal for use in NBRSA and IBS registered benchrest shoots. Made of Leather (suede). Note: Sand required to fill bag.