Camco RV Vent Cover Increase your RV's AC and heating efficiency. 's reflective surfaces block 100% of the sun's damaging rays, helping to keep your RV cooler in summer and warmer in winter. Reflective thermal barrier mounts securely with hook-and-loop strips. 17.5" x 17.5" Blocks 100 percent of the sun's damaging rays Helps to keep the RV cool in summer and warm in winter ...