In our impression, car bumper understands from literal, be sure for car itself namely. Here small make up should correct a concept, the car bumper that we often think is the one part of the bumper on real significance only, it is bumper only surround. Figured out its real fixed position, so why is bumper surrounded should use plastic and either does high strenth material come character " safe " ? Actually this bumper is surrounded do not use insurance, it is a pedestrian however " safe " , can be in character with plastic material buffer adds when producing collision, reduce the harm rate to the pedestrian. If used high strenth data, it is fall in condition of low speed travel, bump into the pedestrian likely also very badly. The character of plastic itself decides it has fight concussion ability certainly, still can bear inside limits, encounter when bumping, OK and automatic spring back carries original figure. And if be dropped by loiter lacquer the high strenth capable person that also compares metallic and so on is handled more easily character, won't produce oxidation reaction to rust with air, the new spray paint cost that handles way is cheaper also. Car bumper is surrounded with plastic and easy production, mould cost also is met fewer, the operation that note model also has the good point with high overall material utilization factor, horny flotsam can use the edge to be not wasted. And if produce attaint to also need not make Ban gold, change component cost also is met lower, material of this bit of high strenth is washed-up.