Your search for "gauges" revealed the following:
Brooks Instruments 1350G & 1355G Glass Tube Variable Area Flowmeters (Rotameters)
S$1,700.00
Vendor: APSS Store
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Brooks MT3750C Metal Tube Variable Area Flowmeter (Rotameter)
S$1,170.00
Vendor: APSS Store
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Brooks GT1600 Industrial Glass Tube Variable Area Flow Meter (Rotameter)
S$1,700.00
Vendor: APSS Store
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