A hand operated flexible bulb for use with a liquid dipensing apparatus 5, the bulb comprises an open ended neck 2 which is securable in an air tight manner to a liquid dispensing apparatus. The flexible bulb is provided with an air inlet 6 separate from the open ended neck, the air inlet having a valve 7 associated therewith such that on application of hand pressure to the bulb, the valve closes to force air through the open ended neck and on release of pressure, the valve opens drawing air into the inlet.