Filson too hot for here. But in my mesh vest I carry a Camelback for water along with a couple more frozen water bottles in my game bag to keep birds cool and for supplemental drinking water , couple high calorie snacks, Baseplate compass and map. Signal mirror and whistle, Leatherman tool, LED head lamp, hair pick for flicking Cholla burrs off me and the dog (passed away this summer). Shell belt with full box of 20ga (we have generous limits and plenty birds some years when it actually rains with a few extra shells for the rattlesnakes). First aid kit to patch up leaks from catclaw acacia, cholla, and other assorted cacti. Wear my shooting glasses full time. Can't start a fire here for fear of burning down the state most seasons so don't usually carry fire starters. Plastic bag to pick up trash and most important - a partial roll of toilet paper.