Patent ID: 8057567

Claim:
A breather cap comprising: a housing including a first port arrangement and a second port arrangement, the first and second port arrangements configured to enable gas to flow between the first and second port arrangements in a first direction and in a second direction; and a filter element operably installed within the housing intermediate the first and second port arrangements to enable gas flowing between the first and second port arrangements in either the first or the second direction to flow through the filter element, the filter element including a first media layer and a second media layer, the second media layer including a thermally bonded sheet, the sheet comprising: (a) about 10 to 90 wt % of a bicomponent binder fiber having a fiber diameter of about 5 to 50 micrometers and a fiber length of about 0.1 to 15 cm; and (b) about 10 to 90 wt % of a media fiber comprising glass fiber having a fiber diameter of about 0.1 to 30 micrometers and an aspect ratio of about 10 to 10,000; wherein the second media layer has a thickness of about 0.1 to 50 mm, a solidity of about 1 to 25%, a basis weight of about 2 to 1000 g-m âˆ’2 , a pore size of about 0.2 to 100 micrometers and a permeability of about 0.1 to 500 ft-min âˆ’1 .