Living in Florida, the temperature today was 92 with high humidity when I went out at 8am to do my lawn work. Typically it takes me 40 minutes and I'm hot, sweaty and exhausted (I'm a 70 yr old female). But, today, put the vest in a bowl of ice water, put a sweatband on my forehead, donned my hat and worked outside from 8am to 1pm and stayed relatively cool. Mowed, weed-wacked, edged, pulled weeds, trim bushes and did general outside maintenance for 5 hours in 92-95 heat -- heat index said "feels like 110". The vest is made out of chamois which does the job quite well. I wore a swimsuit with spandex shorts and put the vest over the top. Did redip it a few times in the ice water. I had another vest with the pockets that you put in frozen packs and that was bulky and didn't keep me as cool as this lightweight vest. I would definitely recommend the vest for those who can't handle the summer heat while gardening or even playing sports.