| 摘要 |
<p>An air brick 1 comprising at least one inlet and at least one outlet which are fluidly connected together. The air brick also comprises a means to attach a screen 2 to the air brick. The screen is attached in such a way that the screen covers at least one inlet and/or outlet. The screen may be provided with at least one aperture such that the size of the objects that can pass through, the object could be for example a small animal, is restricted. The screen may be a mesh, which may be integral to the air brick.</p> |
