Heavy Duty Polythene Bags 500 Gauge Keeps substance clean, dry and in sight. No trouble to secure with a bag neck sealer, heat sealer or tying tool and great for either grouping components together or keeping pieces separated. Manufactured from high quality, clear polythene, these 200 gauge medium duty polythene bags come with a multitude of uses. This gauge is the most popular choice for general food packaging, DIY, retail display, bolts, fixings, panels and kits etc.