plastic parts 1.different models/diameters/sizes etc 2.high quality 3.advanced equipment 4.use PBT,PP material 1.different models: 2U, 3U, 4U spiral shape, insert etc.2.color: any colors.3.material: use PBT, PP, etc.4.high quality, advanced equipment5.different diameters/sizes etc plastic parts for all kinds of energy saving lamp