Good quality, economical hand operated air/vacuum pump is easy to operate. Each squeeze of the pump delivers approximately 15ml, and can be used to create vacuum of 15mm Hg, or air pressure of about 2 atm (standard atmosphere). Pump features a gauge along with a removable cap and elastic valve to provide quick vacuum release without dismantling the pump from the line. Recommended for general laboratory use for applications that do not require high or precise vacuums.