Will IVAR Shelving unit, pine, 35x11 3/4x70 1/2 " fit in an Audi A4 Avant 2022?

The A4 Avant pairs a wide mouth with real height: the opening measures 40⅛″ across and 33½″ tall, so upright boxes pass through without a tilt. The floor gives you 41⅜″ with the rear seats up and 72″ once they fold, a gain of 30¾″, with 39″ between the wheel arches at the tightest point. The lift-over sits at 24¾″ and the floor is only 2″ below it, almost level, so long boxes slide in instead of dropping in. Tall furniture cartons and long flat packs both do well here; extra-wide boxes meet the 39″ pinch first. Slide heavy loads across the sill on a blanket rather than lifting them over.

The IVAR shelving unit packs into one long, slim box: 70 1/2 inches long, 3 1/2 inches wide, and just 1 3/4 inches thick. At 6 lb 1 oz it is light, so the problem is never the weight, it is the length. That 70 1/2 inches of rigid pine will not bend around a wheel arch or a seat back, so a short boot forces it across the cabin at an angle. An estate or a hatchback with the rear seats down takes it easily. Load it flat and straight, thin edge up, and rest the far end against a seat back so it cannot slide when you brake.