{HEAD ~ An emergency basement exit} 3, wherein {TAIL ~ said window} includes two hinged sashes both interconnected to said at least one tread and both arranged to open as said at least one tread is pivoted downwardly 
{ HEAD ~ An emergency basement exit } 3 , wherein { TAIL ~ said window } includes two hinged sashes both interconnected to said at least one tread and both arranged to open as said at least one tread is pivoted downwardly
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