The Trelleborg POLYPAC® - Balsele is a compact rod seal consisting of an elastomeric sealing element and an integrated fabric reinforced base. Due to the radial pre-load an excellent sealing performance will be achieved even at low pressures. The fabric reinforced base prevents the seal from extrusion.--Polypac® Balsele is a compact rod seal consisting of an elastomeric sealing element and an integrated fabric reinforced base.