I would increase the water to 6 gallons minimum up to about 10 gallons if possible. Rotate this water on some sort of schedule. My wife and I keep 21 gallons of water which we rotate every 6 months.

Heavy leather gloves are a good idea for moving rubble etc.

Otherwise it looks like you have a good start. My kits are never done, always in a state of flux.

A pump type water filter would be a good addition allowing you to filter other sources of water. You can also use Toilet tank water, hot water heater, filled tubs etc as additional fall back storage.

A small bottle of bleach is a good addition.

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