Your search for "tubes" revealed the following:
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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Stainless Steel Swagelok Tube Fitting, Male Elbow, 1/2 in. Tube OD x 3/8 in. Male NPT
S$34.66
Vendor: APSS Store
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