The MSR Advance Pro 2 is an ultralight single-wall mountaineering tent built for cold, dry high-altitude conditions, weighing 1446 g packaged (1304 g minimum, 723 g and 652 g per person respectively). It uses just two Easton Syclone composite poles, which cuts pitching down to a fast, simple process — a real advantage when a storm is closing in at altitude and you need shelter up quickly.
Floor area is 2.23 m2 with a peak height of 112 cm, one door, and a 3000 mm water column floor rating; two vents help manage the condensation that single-wall tents are prone to in humid conditions. Fly fabric is 20 denier over a 30 denier floor — light but not delicate — and the space efficiency figure of 1.54 reflects a tighter, more minimal footprint than tents built for comfort. This is a tent for high-altitude expedition use in cold, dry air specifically; single-wall construction manages condensation poorly in warm, humid 3-season conditions, so it's not the right pick for lower-altitude, wetter trips.