The Gregory Z 40 Pack falls somewhere between a daypack and a weekender. It can take you and your gear on a day trip up an ascent or on an overnighter when the weather is calm and not much gear is required. No matter your trek, trail, or ascent, the Z 40 Pack features advanced suspension that keeps you cool as you move. Push farther and faster with ventilated EVA foam on the hip belt and shoulder harnesses providing you with ultimate comfort. And with an interior hydration sleeve with a hose port, you'll stay hydrated along the way.