This tray was manufactured for one of Americal customer,I t's the frame for the Medlaw billboards, because the tray is very large, it is 1m, flat and a little thin, customer was very concerned warp for the tray, we made mold flow analysis to verify warp before mold making, then our professional technical deparment adjust different injection molding parameters according to their experience during injection production, the tray is very flat without warp in the end, the customer was very satisfied with the mass products, he also mailed a gift to us from US.