风向标
air sock //
→another name forwindsock
An Air sock is a textile or fabric duct used for draught-free air distribution and delivery of conditioned air as an alternative to traditional spiral or rectangular steel ducts with grilles and diffusers. Fabric ducts are usually cheaper in material cost, and are quicker to install than conventional metal systems.
... sock词组用法总结 ： air sock 风向标,风(向)袋... bobby socks 短袜 ...