The Valve-Type Paper Poly Woven Bag is one of the most widely used paper-plastic compound bag solutions for bulk dry and flowable products requiring high-speed automated filling. Designed for compatibility with impeller and air-packer filling machines, valve-type paper poly woven bags are filled through a horizontal filling spout that inserts into the valve opening. Once the bag is released from the filling machine, the internal pressure of the enclosed product causes the valve to automatically seal shut creating a clean, dust-free, tamper-evident closure without any additional sealing equipment. Available in 3-layer, 4-layer, and 5-layer configurations with brown or white kraft outer surfaces and optional PE or perforated paper liners.