| 摘要 |
The invention relates to chambers which are sealed against ingress of water and are provided with an element through which air may permeate to equalise pressures of air inside and outside the chamber. The element is of a foamed silicone and has a cellular fine pored layer of predominantly open cells having a skin to be contacted by air outside the chamber. Examples of chambers described and claimed are a vehicle horn and a vehicle headlight. |
