Skip to main content
Official alerts first: NOAA/NWS · FEMA · Ready.gov · follow local emergency management orders.
MMe OffGrid

Interactive tool

Solution Finder

Pick what you need to do and what you have. We'll show what works — most reliable first.

1 · What do you need to accomplish?

2 · What materials do you have?

Matching techniques (1)

Conditional

Water-Filled Bottle Lens

Works only in strong direct sun with a well-rounded bottle or bag. Learn why it often fails.

Also possible if you find…