• Manometer, range 25-0-25, 11 oz water or mercury required
• Rolls up for easy storage and transport
• Over pressure safety traps to prevent loss of fluid due to over range pressures or surges in pressure

The Series 1211 Slack Tube Manometer is as accurate as the finest laboratory "U" gauges, but is designed to roll up compactly for easy carrying. These manometers cover a wide range of pressure readings from 4-0-4 inches up to 60-0-60 inches.

Dwyer Slack Tube Manometers are as accurate as the finest laboratory "U" gauges - yet they are made to roll up compactly for easy carrying and to withstand rough usage.

Simply unroll the Dwyer Slack Tube Manometer and set up to read static pressure, vacuum, or differential pressure. Magnetic clips hold it firmly to any steel surface or hang it on a nail. Turn connectors one revolution to open. When the pressure is imposed, add the number of inches one column travels up to the number of inches the other column travels down. When reading is completed turn connectors to seal columns, roll up manometer into compact coil and tuck it away in its circular metal case or a tool box. No fluid lost. No loose caps or inserts to lose.

Dwyer Slack Tube Manometers cover a wide range of pressure readings from 4-0-4 inches up to 60-0-60 inches. Use them in determining velocity and static pressures, for leakage, fan and blower tests, calibrating control devices, checking gas pressure and many other applications.

All models have flexible vinyl-plastic columns and flexible spring steel scale calibrated in inches of water using water, and inches of mercury using mercury. Scale is center-mounted between columns to eliminate parallax error and has a full 2-inch sliding zero adjustment.

All Dwyer Slack Tube Manometers feature exclusive molded nylon tubing connector assemblies with rapid shutoff design in an unbreakable molded top. One turn counter clockwise and the instrument is ready for use. Another turn seals the tubes completely. Molded all-nylon construction makes this assembly corrosion-proof leakproof and practically unbreakable. Tubing connectors extend horizontally allowing 360° freedom. Tubes will not bend or pinch off.

All models have over pressure safety traps in the top of both columns to prevent loss of fluid due to over range pressures or surges in pressure.

Slack Tube Manometers are suitable for total pressures to 50 psi and vacuum not exceeding 20" Hg. (10" Hg absolute). Can not be used with 0.826 sp. gr. red gauge fluid; use only water or mercury.