The collection bag is flat when empty and easy to store. When in use, the free-standing design stays upright and is stable, requiring minimal space in a refrigerator. Strong, thick co-extruded laminated plastic fi lm that will not rip, tear or wrinkle even under heavy weight or stress. The bag is made of UV resistant materials, which makes it appropriate for testing light-sensitive analytes.Funnels sold separately Supplied in packs of 30