SealLine Black Canyon Dry Bag

Backcountry.com says:
SealLine makes the classic Black Canyon Dry Bag with PVC-free double-coated nylon to protect the environment while it keeps your gear dry. Chose from a wide range of sizes to fit your needs, and take comfort in knowing that SealLine's Dry Seal, dual-strip closure won't let in so much as a drop of water if you flip your boat.