From two hours – to two months, the best Packs

TWO HOURS

CHICOBAG’s DayPack rePETe, made of 95 percent recycled content (mainly water bottles), easily swallows a couple of snacks, a Sigg, and some sunscreen for a hike or bike ride. Back at home, you can stuff it into the small attached pouch. Other niceties include stretchy bottle pockets and a carabiner that’s 97 percent recycled aluminum. ChicoBag was started in 2004 after its founder, Andy Keller, toted some trash to his local landfill and was horrified by the mountains of plastic he saw. 5.6 ounces; holds 20 liters; $20; chicobag.com

TWO DAYS

When you’re up for an overnight trip, the easily compressed JANSPORT Salish keeps you light on your feet. It features a hydration tube, a padded back and belt, a detachable hood, vented shoulder straps, conveniently placed compartments, and several lashing points. JanSport raises funds for, and donates gear to, Big City Mountaineers, a nonprofit that takes urban teens on wilderness adventures. 59 ounces; holds 34.4 liters; $120; jansport.com/cloudripper

TWO WEEKS

Packs from GREGORY MOUNTAIN PRODUCTS are PVC-free, recyclable, dyed via a water-saving process, and designed in an eco-friendly office. The men’s Baltoro 70 and the women’s counterpart, the Deva 70, feature hypercomfortable suspension systems whose adjustable straps make it feel like the pack is giving you a firm but gentle hug. They’re ideal for a fortnight, especially if the rest of your gear is on the smaller side. Baltoro 70: 85 to 94 ounces; holds 68 to 76 liters; $290; Deva 70: 85 to 91 ounces; holds 69 to 74 liters; $290

TWO MONTHS

Most long-term trekkers plot out resupply points and thus don’t need to truck a huge load on their back. They look instead for the latest, lightest technology to help them make it safely from port to port. Durable ARC’TERYX Altra models are just about perfect. Their clever suspension system lets in plenty of air, while a rotating disc transfers the load in harmony with the body’s movements. Arc’teryx employs an independent auditor to help the company “substantially reduce the total amount of materials used over time.” 76 to 81 ounces; holds 62 to 75 liters; $375-$400; arcteryx.com