Polyethylene, dye and ink.
Caution: for use in microwave, place bag on a microwave-safe dish. Handle with care. Bag and contents may be hot. Do not overheat contents as bag may melt. Ziploc bags are reusable after hand-washing and drying! we do not recommend reusing ziploc bags after storing raw meat, fish, eggs, or potentially allergy triggering foods. Warning! to avoid danger of suffocation, keep bags out of the reach of children.