108 without shifting during transport base frame 108 is preferably mounted with a leading corner 128 affixed to tow bar 106 mounting can be accomplished by bolting base frame 108 to tow bar 106 but is preferably accomplished by welding base frame 108 to tow bar 106 and axle 102 alternatively it can be mounted through the use of permanent rivets or bolts and nuts with lead corner 128 affixed to tow bar 106 side corners 130 align with axle 102 inside of wheels 104 side corners 130 of base frame 108 are also preferably mounted to axle 102 by welding rivets or bolts configuring base frame 108 with respect to axle 102 and tow bar 106 as described results in portable structure 10 sitting at a 45 degree angle to leading corner 128 bisected by an axis through tow bar 106 this alignment results in natural wind flow deflection to the sides of portable structure 10 the deflection occurs at a gentle 45 degree angle as the wind hits leading corner 128 and a corresponding corner of portable structure 10 the wind then flows evenly and gently across the angled sidewalls of portable structure 10 affixed to trailer 100.