Lowepro's launched a slew of new photo bags at PhotoPlus Expo including its Pro Trekker AW Series photo backpacks.

The Pro Trekker AW back packs are the latest iteration in Lowepro's flagship Trekker line which was introduced back in 1984. Designed for outdoor and nature photographers hauling their gear over long distances, the Pro Trekker AW is about a pound lighter than its predecessor as well as being slightly lighter in color.

Pro Trekker AW packs are differentiated by model numbers corresponding to the size of the lens it can carry. The 400 AW ($280), for instance, can fit a 400m lens attached to an SLR body.

The new packs have a 10-point adjustment system with Lowepro's "Pack Jack" tool which lets you change the height of the shoulder strap.

The pack's waist belt is removable which is a a plus during traveling since it avoids snags in the airline overhead luggage compartment. When removed the belt can also double as a work belt or a Batman-style "utility belt." (Yeah, that's a bit geeky.)

There are grab handles on the top and both sides of the Pro Trekker AW for easy carrying. A traditional back pack lid on top adds another layer of protection against the elements and a barrier for potential thieves.

Large U-shaped zipper pulls let you get inside the bag quickly while wearing gloves while the zipper themselves are weather-resisant to protect against leakage.

Other useful touches on the Pro Trekker AW line include a 15.4-inch removable laptop sleeve and four options for carrying a tripod. If you get thirsty during a long photo trek, there's a hydration-ready pocket to load in a water bottle with a straw.