Crown International, custom pistons are manufactured from high quality aluminum alloy as per International Standards. Accuracy is maintained in all fronts:- Weight, dimensions, raw material to provide best working and reduced friction and non expansion of custom pistons. Crown International, custom pistons are manufactured from high quality aluminum alloy as per International Standards. Accuracy is maintained in all fronts:- Weight, dimensions, raw material to provide best working and reduced friction and non expansion of custom pistons.