Gregory Z35 Pack – Vassar Outdoors。The Gregory Z30 is a fully featured daypack on the larger side, providing exceptional comfort and versatile load carrying capacity. Very similar in features to the Osprey Stratos 24, the Z30 has a ventilated back panel and a clever pole/ice axe attachment. Unlike the Stratos, the Z30 can hold additional weight comfortably without throwing the weight too far back and putting you off balance. The Z30 also has easier to access pockets for organization. It is more than twice the weight of a pack like the Deuter Speed Lite 20, which is smaller but can carry things lashed to the back. The Z30 is not as convenient for travel as the Patagonia Refugio, but it is one of the most comfortable packs for carrying larger loads while day hiking.