• 9366 Deerwood Lane N Maple Grove
  • 763-425-7890 / 800-328-2350
  • sales@pfcequip.com

Our Customers’ Needs Come First

FSI filter bags has complete, in-house control of the production of every filter bag from fiber processing to final product, resulting in highest quality with cost savings passed directly to you. Our felt bags come in a variety of materials and a wide assortment of collar and ring types that ensure compatibility with most bag vessels on the market. And most filter bags come standard with the patented Polyloc® sealing ring that provides a complete hermetic closure and eliminates the possibility of migration.

Multiple filtration uses require multiple filter types. Extended Life designs offer longer life and fewer change-outs with twice the dirt-holding capacity of standard felt bags. Multilayer designs provide high contaminant loading and long service life. The BOS Polymicro® filter bags offer absolute-rated filtration down to three microns, and an entirely seamless design for more precise filtration. The Heavy Duty Extended Life (BOS MAX) filter bag offers greater depth filtration than conventional filter bags.

If your application requires the ease-of-use of a FSI filter bags system with the high performance of a cartridge filter, Pall’s Marksman™ Series of filters may be just what you are looking for. Marksman filters provide customers with a cost-effective alternative to bag filters.

FSI Standard Felt Bag


  • We offer a full line of felt materials and micron ratings
  • Conventional sewn bags or the PolyWeld® welded seam bags available
  • FSI PolyLoc® ring or other common bag rings available on most bags
  • Heavy Duty and Extended Life designs available to suit your filtration needs
FSI Filter Bags

FSI Polyweld Bag


  • Welded construction of bags completely eliminates unfiltered liquid bypass from occurring due to needle holes
  • Available in standard polypropylene, polyester and extended life felt for broad range of product compatibility
  • Glazed finish eliminates fiber migration for clearer results
  • PolyLoc® ring creates a hermetic seal that prevents liquid bypass and produces clearer results
  • Polypropylene is FDA food grade compliant to government standards
  • FDA Compliant Polyester felt is available (non-standard)
  • Silicone free to eliminate cratering for improved surface results
  • Available from stock for quick delivery
fsi filter bags
FSI Polyweld Filter Bags

FSI Extended Life Filter Bags


  • Excellent filtration on many contaminants – gels, particles with wide range of sizes and particles with irregular shapes
  • A coarse inner layer, graded pore structure, greater depth than standard bags provides excellent filtration performance
  • Available in polyester (PEEX) and polypropylene (POEX)
  • Twice the standard dirt-holding capacity of traditional felt bags to provide longer service life, fewer change-outs and reduced waste
  • Polypropylene bags are FDA compliant
  • Micron rating for polypropylene 5-100; polyester 1-100
  • PolyWeld® seam construction with hermetically sealing Polyloc® ring eliminates liquid bypass
  • Glazed finish eliminates unwanted fiber migration
fsi filter bags
FSI Extended Life Filter Bags

FSI Max Pong Filter Bags


  • High-efficiency, low-cost filtration is ideal for continuous flow applications
  • Welded seam construction eliminates unfiltered bypass due to needle holes
  • Large dirt-holding capacity and lower pressure drop provide long service life
  • Adsorbs smaller particles and filters wide range of particle sizes
  • Pure polypropylene microfiber insert contains no sizing, bonding adhesive, resin, lubricant, silicone or antistatic chemicals
  • FDA compliant to meet food grade government standards
  • PolyLoc® ring creates hermetic seal to prevent liquid bypass
fsi filter bags
FSI Max Pong Filter Bags

FSI Polyfold Filter Bag


  • The dual-sided, extended life felt construction provides maximum dirt holding and a high flow rate
  • 240% more surface area than a standard bag
  • Fits in a standard basket, so no retrofit is required
  • 4X+ dirt holding capacity* results in longer life and fewer change outs
  • Polypropylene center tube supports filtration media, aids in insertion of filter bag, and accepts a bag magnet
  • PolyLoc® ring eliminates liquid bypass
  • Mesh cover assists in insertion and removal of filter bag

*Compared to a standard felt bag. Based on lab testing using water and test dust.

fsi filter bags
FSI Polyfold Filter Bag

About Polyfold™ Filter Bags

The PolyFold™ is our proprietary filter bag constructed of dual-sided extended life felt.  It features 2.4X additional surface area for high dirt-holding capacity and long service life.