Pumps are durable, and light in weight. Will attain and hold vacuum of 25ó Hg quickly and easily. No. 741-000-11 has pumping rate of 15 ml/stroke and 3 psi positive pressure at the exhaust port. No. 741-000-13 has 36 ml/stroke and 7 psi. All units are supplied with a removable safety cover on exhaust port and trigger to release vacuum without disconnecting pumps from the line. A vacuum gauge is supplied to monitor both inches and centimeters of mercury. Styrene gauge housing. Pump comes complete with 2-ft. length of Nalgene 8000 clear plastic tubing.