graded-density skin

例句：

1. 1.The new model's graded-density skin is said to be more durable than its predecessor.
   这款新模型的分级密度皮肤据说比前一代更耐用。
2. 2.The engineer used a special material to create a graded-density skin for the car.
   这位工程师使用了一种特殊材料来为汽车制作分级密度皮肤。
3. 3.The graded-density skin on the helmet provides excellent protection against impacts and injuries.
   头盔上的分级密度皮肤提供了极好的防冲击和保护。