Ceiling set. Four panels, 64 x 149, changed together. In a downdraft this media does the pressure-distribution work: it turns fan output into an even, low-turbulence air column across the booth footprint. Uneven loading between panels is visible in the finish before it is visible on a gauge, usually as dust landing in one quadrant of the vehicle.

Airflow check. The cheap diagnostic on this booth is a smoke pencil under each ceiling quadrant after a set change and again mid-life. Drift toward one wall means either a loaded panel or an exhaust-side imbalance, and it costs nothing to check.

Exhaust side. The AFT listing documents the ceiling only, so exhaust media, fiberglass arrestor or pocketed paper by preference and paint volume, is cut to your measured openings. Send dimensions once; the fitment record keeps them.

Second stage. Whether a given Ultra installation runs second-stage exhaust media is not documented in the catalog record. If your booth has a second bank behind the arrestors, include it in the fitment check so the kit covers both stages.

EPA 6H compliance for area-source refinishers rides on operating a filtered booth per manufacturer specification, and on most audits the question reduces to whether exhaust filters are in place, correctly sized, and changed on evidence. OSHA 29 CFR 1910.94(c) governs the ventilation side: the booth must keep design airflow at the working zone, which is exactly what loaded ceiling or exhaust media erodes. NFPA 33 adds the fire-side requirement to change arrestors before overspray accumulation becomes combustible loading. Correct fitment plus dated change records covers all three with the same paperwork.