It’s always great when summer arrives, but not so great when the mosquitoes arrive. If you travel to a tropical country, it’s always mosquito season, plus the bugs carry nasty diseases, so three months of annoyance turns into year-round danger.

Thankfully it’s easier to keep the bugs away than it used to be if you pack the right clothing. This pair of ExOfficio Altyn Insect Shield Pants is going with me to the coast of Mexico and the jungle of Belize this summer. They’re great travel pants on their own, but the kicker is built-in Insect Shield repellent that stays active for 70—yes 70—washings. I don’t think I have many pants that have been washed that many times, so let’s just say “effective as long as they still fit.”

I’ve used lots of ExOfficio BuzzOff items over the years and they’ve been quite useful. The Insect Shield line is just a step up from that, the repellent staying active longer. I gave these pants a test run when I was out working in the yard and they came through well: not one of the mosquitoes buzzing around ever landed on the pants. There’s no smell, no sign that the stuff is there, but it works.

Besides all that, these are easy to pack. They’re incredibly lightweight, as in less than your average cotton t-shirt. You get a partial elastic waistband, a zippered security pocket, and and the great benefit of quick-dry action when you wash them in the sink. Wrinkle-resistant too, so you keep looking presentable.

They come in khaki or gray, in multiple sizes and lengths, and don’t have that swish-swish synthetic feel that some cheaper travel pants do. There’s also a Convertible Pants option if you want to go double-duty and have some shorts at the ready too. (That one also comes in a women’s version)

See all the specs for the ExOfficio Altyn Insect Shield Pants at the ExOfficio site.