Vacuum demand flow valve

A valve comprising:

• a housing defining a passageway between an outlet opening and an inner opening, and a member being deflectable from a first position to a second position associated with said housing;
• a stop connected to the deflectable member, wherein when the deflectable member is in the first position, the stop is in sealing contact with the inner opening to close the inner opening, and when the deflectable member is in the second position, the stop is spaced from the inner opening to open the inner opening;
• and
• a vent operably associated with said stop where said vent comprises a vent passageway and a vent member.

A flowable material delivery device comprising:

• a first chamber under ambient pressure, the first chamber defining an outlet;
• a second chamber containing a reservoir of flowable material which is vented to maintain the second chamber at a pressure at least substantially equal to ambient pressure;
• an opening connecting the first chamber and the second chamber;
• and
• a deflectable member positioned in the opening between said first chamber and said second chamber and moveable from a closed position to an open position when a pressure less than ambient pressure is applied to the first chamber wherein the flowable material flows from the second chamber through the outlet.