| 摘要 |
A drainage device comprising an improved vacuum regulator assembly is disclosed which includes an adjustable knob for indicating the degree of vacuum being applied to the device from a number of incident viewing angles. Similarly, a vacuum indicator assembly is provided for indicating the presence or absence of vacuum being applied to drainage device. The indicator assembly provides an indication of vacuum inside drainage device from many viewing angles and includes a base defining a recess having a slanted surface with a vacuum symbol which is selectively masked by a collapsible thimble when vacuum is applied or removed from the drainage device. |
