FICTIONAL DEMO — NOT SENT LOADFORM / Paper valve sack study A multiwall paper sack concept focused on filling access and the buyer's closure review. DEMO outline: 600 × 400 × 100 mm Concept material: Multiwall kraft paper Review point: Valve and closing method Barrier and rating: Not specified or validated Layer count, moisture barrier, compatibility and capacity are project-specific. The image supplies no test or compliance evidence. No certification, performance rating or supplier request is implied.