Very Happy with the quality and thickness of these Drop Ceiling tiles. I purchased the 2 x 4 panels and they fit perfectly in the grid. The grid ceiling in a sunroom had an insulated type panel with a deteriorating vinyl lining. I installed these under those in order to maintain the insulation properties and it worked better than expected without bulging. These are less than half the cost of a competitor product of the same thickness. I highly recommend this solution for anyone who wants to update their drop ceiling grid panels.