Constructed with an outer shell of heavy-duty nylon, the Lid Lugger Max offers pre-curved shoulder and belt straps designed specifically with motorcyclists in mind. We particularly liked the adjustability of the straps at the top of the shoulders, which kept a variety of shapes and sizes centered on the rider's hips. By keeping the weight low, back and shoulder fatigue are rarely an issue while riding--even with a ridiculously heavy load. The chest and waist belts keep the pack in place once everything is adjusted correctly, although the chest strap tends to flap at speed. (This might be an annoyance for those with sensitive nipples.) The sturdy dual-density foam backing keeps oddly-shaped cargo from jabbing the rider while helping the pack retain its shape even when lightly loaded.